SMTP Proxy Daemon on Android

I need to develop an Android Application for my Master Thesis that allows users to send emails through a service that performs some filtering and modifications to the mail content before sending it.

For this matter, I see two alternatives: either implementing this on top of an opensource email client (such as K-9 Mail) or by developing a transparent SMTP proxy service. Since no changes (besides configuration) in email clients would be required for the latter, this would be the preferred solution.

As I am a newbie to Android Development (I know the principles of Activities, Services, etc but no real experience apart fro开发者_C百科m "Hello World" tutorials), I would like to ask if is it feasible to consider developing an SMTP proxy daemon-like service on Android, and how can I do it, since it has been very difficult to get help in this topic.

Thankful in advance (and sorry for my sloppy english).

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Step #1: Find an open source Java SMTP proxy server, such as this one or this one.

Step #2: Try compiling the source code as part of an Android project and fix any compilation problems you encounter (e.g., missing classes).

At this point, you will know whether or not it is possible. If things are going OK, then:

Step #3: Create an Android Service that hosts the proxy server.

Step #4: Add in your "some filtering and modifications to the mail content" logic.