Here are some solutions for problem «Gps signal not found» for Android users.
For those who has KitKat and Lollipop:
Install GPS in determining of high precision mode. (sometimes it can solved the problem)
If not than necessary to open the menu: information about the software – build number. Then click on the “Build number” until notice “Congratulations, you are now a developer.”
Go to the menu “For Developers” and remove the check mark from the “Fictitious location.” (See if the problem is solved).
Also for Lollipop users alternatively, need to use Wi-Fi network to determine location. Tested.
If you are owners of Android Marshmallow (Android M) you can try the above variants. Either you will need to download the app from the Google Play Store GPS Status & Toolbox. After downloading the application, you must make sure that you have the latest version of Google Map. Next, run the GPS Status & Toolbox, Google map. Both programs should be run in the background. Wait locate and run the game Pokemon Go.
Also you can try to turn off all the permissions in the game, except for location.
Thank you for attention! Write problems on Pokemon GO game and their decisions on our forum. We solve problems together!