Share your experience!
When using my tracks to track my running workout the gps stops tracking when the screen times out. How can I keep the GPS tracking on while the screen goes off?
I have a Sony Xperia S
I have not used My Tracks myself. I have installed it now and will try to remember to use it on my way home from work today.
Have you tried to use different apps for this purpose to rule out My Tracks being the problem? Try e.g. iMapMyRun or any other similar app just to see if you get the same problem or not.
Let me know what result you get and I will do the same when I have tried My Tracks. 
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So, I tried this and it worked just fine as long as the app had the chance to lock position before I started the tracking.
When I tried to start the tracking before the GPS was fixed it didn't record at all. Once it was fixed it recorded just fine, even when they display was turned off.
I tried this in Xperia P but the software should be the same.
Have you had the time to do some of the testing I suggested? 
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I tried iMapRun and it worked. I've just tried to mytrakcs again and it works if the GPS is fixed. I think that was the problem. If i use mytracks and wait for a GPS fix it works.
Thanks Markus for your support!
That's good to know. Thank you. 
Oh, a quick tip - don't forget to stop the recording when you go inside.
I forgot when I was at a friend's place. I looked at the recorded track afterwards. It looks like I've been running around the neighborhood like a headless chicken. 
I guess it would be helpful to have an option to keep the GPS on even though no app is open. That's because I wanted to geotag some photos and I couldn't because map or gps test or other apps are disabling GPS when navigate off of them. Only with track style apps that keep GPS on could help. It would be easy just to have that option "GPS on" checked. Also there is KISS GPS that does the trick. But more apps, more apps for everything...