As Erel suggested, if you have control on your remote server, you could use JRDC2 as a way to send data from local to remote.
Locally, just use an extra field in your sqlite tables where you take note whether it is new data to be synched or already synched data.
The on user request (or at given intervals) check if you have connection and sync the data using RDC2 features to send records.
Locally you could even create an extra table where you take note of all the data you need to sync. It all depends on your application, I guess.