GPS not working, Smartphone seems to work slower

[SonyUser1]

Hello!

Two issues:

1. When I bought my Xperia J/ST26i /Android 4.1.2 the navigation software - NAVIGON select Telekom Edition - worked fine. But now after the update of the NAVIGON software to version 4.8.0 I often have no GPS signal and no location services.
2. The smartphone seems to work slower. I have bought the phone some weeks ago. Will I have to maintan the phone/software regular?

Thank you very much.

[MarlonUk1]

1. try to download test gps on google play. see if you can connect to gps sats, if yes then it would be software problem which can be fixed by reinstalling the app

if not, try to repair your phone using http://www.sonymobile.com/global-en/tools/update-service/

[SonyUser1]

Thank you very much for your reply, nolramlb.

I need a secure step by step instruction to go back before the last installation of software (NAVIGON select Telekom Edition).

I have not installed any GPS test software. Sometimes the GPS works now. The main isssue is that the phone works very slow, e. g. it needs many seconds to change from one screen to another.

I think the best will be to

1. uninstall NAVIGON select Telekom Edition completely via Google play - from where I installed the navigation software update
2. check if the phone works normally

What shall I do if the smartphone doesn't work normally after uninstallation?

Is this issue connected with the Jelly-Bean-Update? I see a lot of threads in this forum concerning Android 4.1.2 (Jelly Bean).

I would appreciate if someone from Sony Mobile answers.

Thank you very much.

[SonyUser1]

Update

1. I have uninstalled NAVIGON select Telekom Edition completely via Google play.
2. I have switched off the phone after uninstallation. To do that hold the switch on the right site until the options menu appears. Then press switch off.
3. I switched the phone on again.
4. After the screen appears Google play updates apps.
5. After that the phone works normally again.

I need the navigation software.Version 4.7 was preinstalled and worked well. But I cannot get it back now.

Question: Can I try to reinstall NAVIGON select Telekom Edition 4.8.0?

Question: Google play was updated. Any issues with the new version?

Thank you