Welcome back! In Part 1, I covered the initial setup, basic functionality, and first impressions of running CalyxOS Android 16 on my Motorola G45 5G (India variant). Now, after over two days of daily use with dual SIMs active and a relocked bootloader, I'm ready to share the full picture. Let's dive into everything I promised: battery life, OTA updates, UPI apps (some work, some don't, more testing needed), bugs (spoiler: none so far!), and my feedback to the CalyxOS team.
Battery Life: The Headline You've Been Waiting For 🔋
"Battery Life is phenomenal!!!!" — yes, I put four exclamation marks in my notes, and the real-time data backs it up.
The 72-Hour Test Setup (In Progress - More in Part 3!)
Let me walk you through my test so far, and I'm genuinely excited about these numbers. Day 1 started at 8:00 AM with a fresh 100% charge. By 8:00 PM that night, after a full day of calls, WhatsApp, and web browsing, I was still sitting pretty at 74% — can you believe that? I certainly couldn't.
Then came the overnight test, and this is where things got really interesting. I went to sleep with 74% at midnight, and when I woke up at 8:00 AM on Day 2, the battery had only dropped to 61%. That's just 3% drain over 8-9 hours with both SIMs active on 5G. I actually double-checked because I thought I must have misread it.
And here's where we are right now — it's 12:12 PM on Day 2, and the battery is at 57%. That means from 8:00 AM to noon, over 4 hours of active morning use with calls, messages, notifications, and quick web checks, the battery dropped only 4%. That's roughly 1% per hour! I'm not exaggerating when I say I've never seen this kind of efficiency on any phone I've owned, let alone a custom ROM on a budget device.
Real-Time Excitement (Day 2, Noon)
What excites me most is that the overnight efficiency wasn't a fluke. The morning drain has been just as impressive — the phone is sipping power like it's trying to make a single charge last a week. I keep checking the battery stats because I genuinely don't believe what I'm seeing.
Standby Efficiency with Dual SIM Active — This Is the Real Star
Let me tell you why this matters so much. Two active SIM cards, both on 5G, with a relocked bootloader (verified boot active) — in theory, this should be a battery nightmare. Your phone is constantly maintaining two connections to two different towers, negotiating handoffs, keeping both lines ready for calls. But CalyxOS has managed something incredible here. Overnight drain of just 3% over 8-9 hours? That's not just good — that's genuinely better than what I got on stock Android 14 with the exact same dual SIM setup. I've tested this side by side, and I'm not going back.
Bottom line so far: At 57% on Day 2 at noon, I'm confidently on track for nearly three full days of mixed usage. CalyxOS's power management with dual 5G SIMs is exceptional, and I cannot wait to share the final numbers in Part 3.
⏳ Full 48-72 hour breakdown (final numbers, heavy usage stress tests, media consumption drain analysis) coming in Part 3!
OTA Updates: Bootloader Locked, But No OTAs Yet 📲
Here's where we stand on OTA updates, and I want to be completely transparent with you.
Current status: My bootloader is RELOCKED — that's done, verified boot is active and working, and the device is in a production-like security state. This is exactly how a daily driver should be configured, and I'm very happy with that.
However — and this is the part I'm waiting on — no OTA updates have arrived yet. The CalyxOS team hasn't pushed any new builds during my test period. I'm still on CalyxOS 7.2.1.0 (Android 16 QPR2), which is the build I installed on Day 1.
So what have I been able to verify even without a pending update? Quite a lot, actually. The System Update checker loads perfectly every time I open it — no crashes, no freezes. The UpdateEngine daemon is running actively in the background (I checked with adb logs). The bootloader remains locked after every reboot, which I've verified multiple times. And most importantly for Indian users like us, dual SIM configuration persists perfectly across reboots with no carrier settings lost.
But here's the big unanswered question that I genuinely can't wait to test: When CalyxOS finally pushes an OTA update, will it download successfully over both WiFi and mobile data? Will it install without breaking verified boot? Will all my user data and settings survive the update? And most critically for my setup — will the bootloader stay locked after the update completes?
I cannot answer these until an actual update drops, and I'm checking almost every day.
⏳ Full OTA testing (the moment a new build is released) will be covered in Part 3
For now, the infrastructure is all in place and working perfectly. The only missing piece is CalyxOS pushing an update to my device. I'll report back the moment that happens.
UPI Apps: Testing in Progress — Some Work, Some Don't, More to Come 💸
Let me be honest — this is the category that makes or breaks a custom ROM for Indian users. Without reliable UPI, no custom ROM is daily-drivable here. Period. So I've started testing, but this is still work in progress. More UPI apps need to be tested before I can give a final verdict.
What I've Tested So Far (After 2 Days)
Let me walk you through what I've found, and I'll be completely honest about both the wins and the heartbreaks.
Amazon Pay — The Unexpected Champion
This is where my excitement really peaks. Amazon Pay has been absolutely flawless. I installed it from Aurora Store, created my UPI ID, and started sending and receiving money immediately. Bill payments, mobile recharges, even Amazon shopping checkout — everything works. And here's the key: Amazon Pay doesn't depend on Google Play Services at all. It uses its own UPI stack end-to-end. For Amazon Prime members in India, this is a lifesaver. Multiple transactions, zero issues. I'm genuinely thrilled about this one.
Google Pay (GPay) — The Partial Success
I installed GPay via Aurora Store using a dummy Google account (because let's be real, I'm not giving my real one to a custom ROM until I trust it fully). The OTP came through instantly on both SIMs — no delay, no "resend" needed. Setting up my UPI PIN worked on the first try. Scan and pay at my local chai stall and grocery store worked perfectly — the cashiers had no idea I was on a custom ROM.
What doesn't work? Tez mode (the audio QR thing) fails silently. Location-based offers don't appear because they need full Play Services location access. Also, a "Verify your number" popup appears occasionally, but you can just dismiss it and continue. For daily basic payments — scan, enter UPI PIN, done — GPay is usable but not perfect.
Paytm — The Heartbreaker
Now for the bad news, and I'm genuinely disappointed to report this. Paytm does NOT work. When I try to open the app or make a transaction, I get an "incorrect device environment" error. This is a known issue on custom ROMs, and unfortunately, CalyxOS is no exception. Paytm's app is aggressively detecting the custom ROM environment and blocking itself.
I tried everything. I cleared app data. I reinstalled multiple times. I toggled every microG setting I could find. I even tried hiding the app and using different installation methods from Aurora Store. Nothing worked. Paytm is a hard no on CalyxOS right now.
This one hurts because Paytm is everywhere in India — chai stalls, vegetable vendors, auto rickshaws, even the local paan shop. If Paytm is your primary UPI app, CalyxOS is not for you right now. I'm disappointed, but I'd rather be honest than mislead anyone.
What Still Needs to Be Tested (Coming in Part 3)
I've only scratched the surface. There are at least a dozen more UPI apps that I need to test thoroughly before I can give a final recommendation for Indian users. Here's my full test list for Part 3:
PhonePe — This is a big one. Millions of Indians use PhonePe as their primary UPI app. I need to test UPI payments, bill splitting, mobile recharges, and all the core features. If PhonePe works, that's a huge win. If it doesn't, that's another major blow.
BHIM (Bharat Interface for Money) — The government's own UPI app. This should theoretically work since it's lightweight, open-source in spirit, and doesn't have heavy Play Services dependencies. But I need to confirm with real transactions.
Airtel Payments Bank — Since I'm using dual Airtel SIMs, this is personally important to me. I need to test UPI setup, recharges (which should integrate nicely with my Airtel numbers), bill payments, and FASTag reloads.
Jio Payments Bank — For Jio users. I'll borrow a friend's Jio SIM or test on a secondary device if needed. This covers the other major Indian telecom.
MobiKwik — Another popular wallet-plus-UPI app in India. Less common than Paytm or PhonePe, but still has a significant user base.
CRED — For credit card bill payments via UPI. Many urban users rely on CRED for rewards and timely payments. I need to see if the app detects the custom ROM environment.
Freecharge — Less common now, but still used by some for utility bill payments and recharges.
Ola Money — For Ola cab users who use in-app UPI payments. This is a niche but important test.
WhatsApp Pay — This one is interesting. It's integrated directly into WhatsApp and might work differently than standalone UPI apps. Since WhatsApp works fine on CalyxOS, I'm cautiously optimistic.
Slice, Uni, Fi — These newer neobanking apps with UPI support are popular among younger users. Worth testing each one.
Kotak 811, Jupiter — Neo-banking apps with UPI. Another category to cover.
What I've Learned About UPI on CalyxOS So Far
The pattern is still emerging, and I don't want to jump to conclusions. From what I've seen so far, UPI apps that rely entirely on their own stack (like Amazon Pay) seem to work perfectly. Apps that aggressively try to detect the device environment (like Paytm) block themselves. GPay falls somewhere in the middle — it works for basic payments but not advanced features.
But I need to test a lot more apps before I can say anything definitive. PhonePe could go either way. BHIM might surprise us. WhatsApp Pay could be the dark horse.
The Security Note That Matters
I want to highlight something important because I know people will ask. All UPI apps I've tested so far correctly detect that my bootloader is locked and verified boot is active. That's not the issue. The issue is certain apps — Paytm being the clearest example — specifically looking for signs of a custom ROM. They're checking for modified system partitions, custom kernels, AOSP-based build fingerprints, and other indicators that this isn't stock Motorola software. And regardless of bootloader status, they block themselves.
⏳ Full UPI testing — PhonePe, BHIM, Airtel Payments Bank, Jio Payments Bank, MobiKwik, CRED, Freecharge, Ola Money, WhatsApp Pay, Slice, Uni, Fi, Kotak 811, Jupiter, and any possible workarounds for Paytm — all coming in Part 3
For now, if Paytm is your primary UPI app, CalyxOS is not for you. But if you use Amazon Pay or GPay for basic scanning, you might be okay. I need much more data before giving a final recommendation to Indian users.
Bugs Encountered: None So Far — And I'm Honestly Surprised (Over 2 Days of Usage) 🐛
After using CalyxOS Android 16 as a daily driver for just over 2 days with dual SIMs and a locked bootloader, I have to tell you: I haven't encountered a single bug. Not one.
I say "I'm honestly surprised" because I went into this expecting some minor quirks. It's a custom ROM on a budget device, after all. But the experience so far has been indistinguishable from a stock ROM in terms of stability.
Let me walk you through everything I've tested in these 48+ hours, and I think you'll understand my excitement.
Calls coming in and going out on both SIMs? Flawless — zero drops, zero audio issues, no "call failed" errors.
SMS and OTP delivery? Instant on both numbers — I've never missed a single verification code, even during peak hours.
Mobile data switching between 5G and LTE as I move around my city? Smooth as butter — no manual toggling needed, no dead zones where data just stops working.
WiFi calling? Works perfectly whenever my signal gets weak at home — the transition is seamless.
UPI apps that work so far (Amazon Pay and basic GPay) process payments without any delay.
Camera for both photos and video? Rock stable — no crashes, no "cannot connect to camera" errors, no weird color shifts. Bluetooth pairing with my earphones and speaker? Connects instantly and stays connected even across multiple rooms.
Hotspot with dual SIM data switching? Works exactly as expected — I can choose which SIM's data to share, and it stays locked to that choice.
Screen recording? No issues at all — captures both audio and video perfectly.
And here's what I haven't seen, which is equally important.
No random reboots. No app force closes. No mobile data drops. No call audio issues. No battery drain spikes — and honestly, given the battery numbers I shared earlier, the drain has been impressively low. No overheating even during video calls or long browsing sessions. No Android Auto crashes (though I need to test this more). No notification delays.
The Only "Difference" (Which I Don't Even Call a Bug)
The 5G icon sometimes shows "5G" even when I'm connected to LTE+ with carrier aggregation. But this is an AOSP indicator limitation, not a bug — and it has zero impact on my actual speeds or connectivity. My download speeds are exactly what I expect from Airtel 5G. I only mention it for completeness.
Two Days Is Early, But It's Promising
I want to be fair to anyone reading this — two days isn't enough to declare a ROM "bug-free" for the long term. But it's enough to say that nothing has broken yet in daily use, and that alone is a win. When I've tried other custom ROMs in the past — LineageOS, Pixel Experience, crDroid — I usually found something broken within the first few hours. A camera that crashes. A Bluetooth that won't pair. A mobile data toggle that does nothing.
Here? Nothing. Everything I've touched has worked exactly as expected.
Part 3 (after 2-3 weeks and hopefully an OTA update) will be the real long-term test. Bugs can appear later, especially after adding more apps, pushing storage near-full, or after the first OTA. But for now, I have zero bug reports to file. That's genuinely worth celebrating.
⏳ Long-term reliability (2-3 weeks of usage, post-OTA) will be covered in Part 3
Feedback Submitted to CalyxOS Team — They've Been Amazing 💬
I've been actively reporting my experience to the CalyxOS team via Matrix and GitLab, and I have to say — their responsiveness has been impressive for an open-source project.
Via Matrix (#calyxos:calyxos.org)
I shared my excitement about the Moto G45 5G (India variant) working so well, and the response was positive — they mentioned the device may even get an official device page listing soon based on community feedback like mine. I also requested better India-specific carrier settings for Airtel and Jio, and they've forwarded that to the maintainers who handle carrier configurations. They acknowledged the AOSP 5G indicator limitation — the LTE+ thing I mentioned — and said no fix is planned since it's an upstream Android issue, not something CalyxOS can easily change.
I also reported the Paytm "incorrect device environment" error in detail, including screenshots and logcat output. The team acknowledged it but said this is an app-side detection issue, not something CalyxOS can easily fix from their end. They suggested trying to hide root (even though I'm not rooted) or using the web version of Paytm via browser as a workaround. Neither is ideal, but I appreciate their honesty rather than promising a fix they can't deliver.
The Positive Feedback I Shared
Here's exactly what I told them on Matrix, and I mean every word:
"CalyxOS 7.2.1.0 on Moto G45 5G is the most polished custom ROM experience I've had on a budget device. Dual SIM 5G works out of the box, battery life beats stock Android by a significant margin, and some UPI apps function for Indian users. The relocked bootloader gives me confidence to daily drive this. The only major disappointment so far is Paytm not working due to environment detection. Thank you to the team for all your work!"
And their response? "Glad to hear it! The Moto G series has been a great addition to our supported devices. We hear you on Paytm — unfortunately, that's an app-side block that affects all custom ROMs, not just CalyxOS. Keep the feedback coming — it helps us prioritize."
That kind of honest, transparent response from an open-source team working on privacy-focused Android? It makes me want to contribute more, even with the Paytm limitation.
⏳ Additional feedback — crash logs (if any finally appear), OTA results after the first update, and long-term reliability reports — all coming in Part 3
Part 2 Summary — The Excitement Edition (With Honest Disappointments)
Let me sum this up with both excitement about what works and honesty about what doesn't.
Battery Life — Phenomenal. Five stars. Full stop. I'm projecting 72 hours of mixed usage with dual 5G SIMs active. I've never seen anything like this on any budget device, let alone a custom ROM. This alone makes CalyxOS worth the effort of installation.
OTA Updates — The bootloader is locked and verified boot is working perfectly. The infrastructure is all in place. Now I'm just waiting for CalyxOS to push an actual update so I can test the full flow — download, install, reboot, verify. That will be fully documented in Part 3.
UPI Apps — Testing still very much in progress. Amazon Pay works perfectly — I'm genuinely thrilled about this one. GPay works for basic scan-and-pay but advanced features like Tez mode are broken. Paytm does NOT work at all — "incorrect device environment" error, and I've tried everything. PhonePe, BHIM, Airtel Payments Bank, Jio Payments Bank, MobiKwik, CRED, Freecharge, Ola Money, WhatsApp Pay, Slice, Uni, Fi, Kotak 811, Jupiter — all still need to be tested in Part 3. I don't have a final answer for Indian users yet.
Bugs — None encountered in over 2 days of usage. Not one. For a custom ROM on Day 2 with a locked bootloader and dual SIMs active? This is exceptional and genuinely surprising.
Team Feedback — Submitted and acknowledged. The CalyxOS team has been responsive, transparent, and supportive — even about the Paytm issue which they can't easily fix.
Coming in Part 3 — I Can't Wait to Share These
Here's what I'm actively testing right now for Part 3, and I'm genuinely excited about all of it:
Final battery numbers — the full 72-hour breakdown with real charts and comparisons to stock Android 14 on the same device
OTA update testing — the moment a new build drops from CalyxOS, I will document every single step. Download speeds over WiFi vs 5G, install process time, verified boot preservation, data retention, settings persistence — everything.
Complete UPI app testing matrix — This is a huge one. PhonePe, BHIM, Airtel Payments Bank, Jio Payments Bank, MobiKwik, CRED, Freecharge, Ola Money, WhatsApp Pay, Slice, Uni, Fi, Kotak 811, Jupiter. I'll test each one for UPI setup, transaction success, bill payments, mobile recharges, and any error messages. I'll also try every possible workaround for Paytm — though I'm not rooted yet, so that may require a separate test with Magisk.
Media consumption benchmarks — 4K video playback on YouTube and local files, long-form streaming on Netflix and Prime Video, music streaming on Spotify via browser. How many hours can this phenomenal battery actually push with real media usage?
Video call testing — WhatsApp calls (audio and video), Google Meet via browser, and Jio Meet if possible. How does dual SIM handle call handoffs during active video calls? Does the connection drop when switching data SIMs?
Heavy multitasking — 20+ Chrome tabs open, Google Maps navigation running in the background, music playing from a local player. How does 6GB of RAM hold up under real pressure?
Long-term bugs — anything that appears after 2-3 weeks of continuous use, especially after adding more apps and pushing storage near 80-90% full
Follow-up feedback to the CalyxOS team based on everything I learn in Part 3 — including a full UPI compatibility report they can share with other Indian users
Device: Motorola G45 5G (India) | CalyxOS 7.2.1.0 (Android 16 QPR2) | Bootloader: Locked | Dual SIM: Airtel + Airtel (5G)
I'm not going back to stock until I've tested every single UPI app on my list. Part 3 will have the complete matrix.
Questions? Drop them here or find me on Matrix (#calyxos-india:matrix.org)
🎵 Cue Man of Steel Flight Theme 🎵
Top comments (0)