So does using these cheap chargers that you find in stores actually

Slow charge is because of low amps

>>52501678
a bad wall-to-USB can fuck with your phone. If the capacitors on the inside are of low quality, the screen's sensitivity gets impacted. So basically, if you use a shitty charger, it'll charge, but your phone will spaz out at you once in a while.

>>52501894
Which part being cheap would mess with your phone? A cheap cable or a cheap wall charger?

>>52502015
Charger, since that is what converts the power. Cables still can to an extent, but not as much as the charger module itself.

>>52502015
The cable's mostly a passive component. Cheap chargers often have absolutely shitty filtering and regulation that let the voltage vary way outside specifications. This can mess with the phone if its USB port is not built defensively enough.

See: http://www.righto.com/2012/10/a-dozen-usb-chargers-in-lab-apple-is.html

it's a dirty dc wave (or the existence of one rather) that most of concern. Dirty ac to dc conversion on cheap ass transformers is common, actual voltage would tend to be fine. Solder job and improper (ie no proper separation high voltage ac and low voltage dc side) are the other big concerns.
Good phone should protect pretty well but obviously they can't shield it against everything. To be fair though it's just not worth the risk using one as a main charger, get a decent one that won't fuck up your shit and will charge it faster.

>parents use cheap shitty dollar store usb wall adapters
>wonder why their phones charge slowly
>chargers reek of electric smoke
Everytime I visit I bring one or two good ones for them since I get so many but they just never use them for long before they switch back accidentally, forget and just accept having to let their phones take 12 hours to charge.

Not usually. I even give my phone 5.6v rather then the standard 5v and it charges pretty fast, no issues after over a year.

>>52502183
Amps are more important than volts

>>52502179
get rid of the shit chargers the next time you give them legitimate chargers

What phones do they use?

>>52501678
Had one explode in my hand as I plugged it in.
YMMV.
They are notorious for poor design, not complying with regs, poor shielding etc.

>>52502208
they're proportional variables to energy delivered, lol

>>52502387
This. Using higher volts gives the charging system more to work with and can compensate for voltage sag that might be induced by shitty cables.

My dad uses one and wonders why my phone charges faster and holds a charge longer.

>>52502179
just take away all of them