so I have an honor 7, had it over 2 years now. It has seen better days, I need a new phone however don't have the money as of yet. The phone must always be connect to a charger, using a fast charging source and cable (I've got decent power bank). If it isn't charging it will turn off almost instantly - always says the power is at 100% - and if it's charging with a non-fast charger, it also turns off. However even while connected to a fast charger if i use it too much (15min) it gets very warm and again, turns off.
I'm looking for as many ways to reduce power consumption as much as possible, but will still allow me to use my phone normally - e.g snapchat - I'm happy to root my phone if it's needed to turn off certain stock apps for example.
Any and all help/advice would be greatly appreciated. Thanks