No. Gionee A1 Lite does not have a fast charging support.
No. Gionee A1 Lite is not a waterproof phone. But it is made of Aluminium Alloy and hence you may get some protection against damage.
Yes, Gionee A1 Lite has 2 dedicated sim card slots and 1 dedicated memory card slot. So, you can use all of them at one go.
No. During our review did not find any major heating issue. However, since the mobile phone is made of Alluminimum Alloy body and has got huge 4000 mAh battery - you may notice some heating issue while charging.