Recommend me a phone that can deal with heavy use

[theleg]

Ok, I need a phone that can handle heavy use...and by that I mean 15 hours a day of use. Fed of having to replace phones because the battery gets destroyed and you cant buy new batterys for phones any more. Can you guys recommend me a phone that can handle that level of heavy use OR a relatively modern phone that has a replaceable battery?

Much appreciated

 

[theleg]

The current one is a galaxy S8 but the battery is dead. Runs out extremely quickly and at random times, sometimes without use. Also resets randomly.