GPS on phone an HR tracking on charge 5? Possible?

[Wraiththe]

Is there a way to use my charge 5 as a HR monitor and the phone as GPS tracker when walking?
I believe you can do it on the watch alone, but it really drains the battery.
Which apps would work best. 
I used to use mapmyfitness and myfitnesspal, but I am strapped and tired of paying for dozens of services.  I have a top of the line android phone and the fitbit charge 5.

Any help would be appreciated.

[LZeeW]

@Wraiththe   The Charge 5 has different GPS settings: dynamic, built-in and phone.  If you always want to use your phone's GPS, please do the following: swipe down on the clock face to the Settings > GPS > set to phone.  The dynamic setting is supposed to use your phone.  But if your phone isn't moving when you exercise, it will switch to built-n GPS.