The app you're looking for is 'Dish for My RV Satellite Finder'. This is for Iphones, although I believe there is one for Android too, but with a different name. Cost is $5.00. Maybe google the developers name to find the Android version.
I've been using it for about 3 months. Works great. It shows both sets of satellites (east and west). It uses the phone's camera and projects 2 sets of 3 red dots when you aim it at the southern sky. A big help if you don't know if your antenna is being blocked by a tree limb. And it's a real hoot to use !
The app seems to get mediocre reviews. All I can say is that it's been well worth the 5 bucks to me. Has not failed me yet.
On edit - I also have one of those golfball satellite receivers if it makes any difference.
Tim