This app was mentioned in 3 comments, with an average of 1.33 upvotes
Install current widget to see the charging current without waiting
https://play.google.com/store/apps/details?id=com.manor.currentwidget
I use my old S2 charger over night. That pushes 820mA to the battery. To check the input, you can use this: https://play.google.com/store/apps/details?id=com.manor.currentwidget
On Android, CurrentWidget works great. It'll even log to a file periodically and graph it back for you.