The two phones I have right now are tbe Samsung J7 Crown I already mentioned and a Moto G6. The Moto has 1 GB more RAM, but I haven’t ran into issues with the 2 GB in the Galaxy. The Galaxy has a much better camera, though, which is important to your document scanning.
You might want to look at the Galaxy A10e. The camera is only 8 MP, but that might be good enough for you.
I would seriously avoid that tiny one at that price. If you could get it as a novelty for $20-$30, sure. But over a hundred dollars for something that will probably last approx. 0.005 seconds before failing?
Non-insanely high-rez photos are around a couple of megabytes each. Non-insanely high-bitrate music is around 1 megabyte per minute. So say (for instance) your phone has 16 GB of usable memory. If you split that 50/50, that will store very roughly 4,000 photos and 5 days of music. But Micro SD cards are very cheap–for $33 you can add another 30 thousand photos and another month and a half of music.
Counting both the built-in undeletable damn stupid bloatware apps that Google/manufacturers/carriers insist on installing and apps I have installed myself I have around 120 apps on my phone taking up around 12 GB of space. Your bittage may vary.
Unless I get some data indicating otherwise, it’s looking like a MOtorola G6 variant vs a G8 variant. Are smartphones like GPUs in that it’s nearly always better to take the most recent one of a series?
Just thought about this issue–if you decide to record video of anything, that takes an obscene amount of memory. At 1080p 30fps, I can only get it down to around 2 MB per second in recording to avoid artifacts. The standard settings are much higher than that, maybe 5 or 10 MB per second. Higher resolutions than that (such as 4k at 60fps) takes much more room than that. You can compress that a lot further afterwards (at a much slower speed) but you need the space for the initial recording.
You want the one with the most recent operating system version, ideally one that the manufacturer will push another upgrade or two to. So, yeah, the most recent one is generally better. Also, the chips have gotten better, so you may get something that’s a little faster for a little less power with a new chip set. That being said, if the older one is a lot cheaper, or has some option you care about, it’s not that big a deal.
Both of these are international versions–be careful to make sure that the phone you buy supports the standard for the carrier that you are going to use. Different carriers use different standards and different frequency bands.