Honestly I tried everything on earth. I have been struggling with this issue for a long time. Things that are worth mentioning:
1. Changing Time out values didn't change anything
2. When the call fails ( or during failure ), browsing the internet from the tablet is no issue
3. When the call fails ( or during failure ), web service is responding other requests from other sources
4. The issue is tablet independent ( the same tablet will work while the other one is not and vice versa )
5. Tried different tablet models and different phones
6. Tried several service providers at the same time, still got the same issue
7. Tried over WiFi and Mobile Networks. Same results
8. calls that I am using are simple HTTP calls nothing fancy ( no file downloads )
Currently I am using some retry mechanism to fix the issue, however it is not perfect. ( it does the job in several cases ), but a delay of a minute ( meaning waiting for a time out to occur ) for a request feels like a year for the end user.
This line below is not 100% sure, I am still trying to duplicate the issue ( but may be will give you some idea )
I have also noticed that in some cases the requests ( including my retries ) all of a sudden appear at the server, all at the same time ( even after the time out occurs on the tablet )
Your help would be greatly appreciatad