re: phone charging question
@Corina@weirder.earth So it depends on what your phone needs and what it supports
Super cheap chargers (which, note, are actually power supplies--the charger itself is internal to the phone) will only provide a tiny amount of current; standard values for USB 2.0 are 100 mA and 500 mA, and you'll commonly see 1 A and 2.1 A as well (these were later extensions to the standard to address phone charging specifically).
A 1 A or 2.1 A charger will almost certainly be able to charge a phone adequately overnight unless the phone is doing something that consumes a lot of power during that time.
Modern devices commonly support one of two major extensions to the idea: either Qualcomm quickcharge (the earlier, less "official" standard) or USB Power Delivery (the later standard). Both of these require support from both the device and the 'charger' (power supply), and they both allow the device to negotiate a higher charging voltage, up to 20 V at 5 A for USB-PD (though this is way more power than a phone would need; that mode is used for charging laptops, phones will negotiate to something like 9 V at 2 A or thereabouts). Power supplies that support these can charge a phone very quickly, but tend to be more expensive.
If you're looking for a cheap way to charge your phone, and you don't need a super fast charge, look for something that can do 2.1 A. I'd go for a brand like Anker if you can, they're known to be reliable and some of the super cheap ones might lie about their specs
-F/R
re: phone charging question
@Corina@weirder.earth oh yeah and if you want to check how well a charger can charge without needing to see how long it takes to charge your phone, you can get usb power meters (this one appears to be the same as the one we have, which works well enough and isn't too expensive) to measure it. Note that any power supply that supports USB-PD will only do so over a USB-C connector, though, so you'll need a different one if you go that route (though I doubt you will, if you want something cheap)
Of course, these power meters are more expensive than a cheap usb power supply, so it's probably not worth it if you just want something that works.
-F