• Scheduler to auto sync pending messages.
• Pending and sent message views.
• Configurable auto-reply messages.
• Instant auto-reply messages from server.
• Import existing messages from inbox.
• Keyword based SMS filtering.
• Multiple languages.
• Task scheduling.
• Multiple Sync URLs.
• Filter by phone number. Either Whitelist or Blacklist a phone number.
• HTTP basic authentication support in Sync URLs.
• Logviewer to see the activities on the application.

Limitations

• Android enforces an outgoing limit of 100 SMS messages per hour. However, there are ways to override this limitation. Check this thread for details.

Caveats

• There may be security holes. Patches are humbly accepted.