change screen resolution - pokerstars app problem


I have a problem with my hi9 plus.
When I install the app from pokerstars it doesn’t run.
After a lot of tests I think the problem it’s on the app. It doesn’t work too in another tablet of a person who test it in their.
I think that the problem it’s in the screen resolution of the tablet.
Can someone tell me how to change the screen resolution ?
Or have someone another idea to solve the problem ?