OK, first 24 hours of usage including quite a lot of screen-on time (for me) setting things up, trying stuff out, installing apps, taking pictures, a couple of phone calls, whatsapp, texts, news feeds & video. Battery down to 68%.
MIUI (Xiaomi's overlay) wants to take over a lot of tasks that might be managed by google/android, including backup of settings and data. All MIUI apps seem to require access to contacts and the ability to make phone calls, as well as getting the user to agree to data acquisition, and refuse to work without being given the un-necessary permissions. I'm finding replacements over time, and will soon begin uninstalling them, but if you're a little concerned about data sharing then you'll probably want to root & flash. I'm not really a fan of MIUI in terms of looks still (but it does provide enormous numbers of options for setting up) and would have probably been happier with a barebones Android install. Never the less I am impressed that Xiaomi keep the systems updated so well. If I didn't mind a slightly larger form factor then I would have definitely bought the Mi A1 with Andoid 1 (i.e. native Android, google only, immediate updates) faster processor etc, but it's quite a lot bigger for the extra screen size. It's presently on Android 7.1 and Oreo is already being rolled out in some places.
Usage-wise, it's quite nice and responsive. Opening applications isn't instant, but neither is it laggy, and animations etc are smooth - it's certainly the most fluid smartphone that I've owned. GPS works well indoors and out, and there's both a gyroscope & compass onboard so the device always knows which way it's facing. I had a quick browse on 4G in Oxford today while waiting for someone, and both Opera mini and the BBC app were fast and smooth. Over wireless, downloads are very quick *for a phone* with a 28Mb app taking a couple of seconds. The fingerprint scanner gets it right every time I put my finger in the right place, opening quickly, and I know that it's already become a habit that will be hard to break on a non-FPS phone.
The screen isn't the brightest, but it's usable in direct sunlight. It's also 780P, but that's fine for me on a 5" screen. Photos seem OK for a phone. Video - no idea. The device itself feels good in the hand, very solid, buttons nice & snug.
*edit* Call quality is pretty decent, and close to the Lumia, although it struggles to get signal a little more than the Lumia did: I can make calls in my livingroom, but need to be aligned with a window. I took a call at work from someone who traditionally tends to break up when on mobile, and there were periods of clarity and periods of breaking up, just like normal. Another call in Oxford was loud & clear. This is probably as good as I could reasonably hope for (I hate calls on any kind of phone).
It's probably comparable to the new Moto E6 plus, which has a similar processor, RAM, slightly bigger battery & screen, but £169 vs £106.
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