OGN tracker (formerly ProxyMaxi) does not collect, save, publish nor share any of its user's private or otherwise sensitive information except for -only if explicitly requested by the user- collecting the GPS position during the entire usage of the app (even while running in the background) and directly transmitting it to the servers of the Open Glider Network. For further information please check the data usage policy of the OGN under http://wiki.glidernet.org/.