English speech to text and text to speech is using att’s api. Seems no limitation(low volume is ok)
Chinese speech2text and text2speech is using xunfei’s api, 500 times per day before submitting the app. Alternative is google’s api, but this api is got by reverse engineering.
Resources about OAuth2:
http://nilvec.com/implementing-client-side-oauth-on-android.html
http://simpleprogrammer.com/2011/05/25/oauth-and-rest-in-android-part-1/
Java upload file using post:
http://www.codejava.net/java-se/networking/upload-files-by-sending-multipart-request-programmatically
add appcompat to workspace
https://stackoverflow.com/questions/26700996/r-java-is-not-generating-due-to-appcompat-v7/26708301#26708301