This is an unofficial application to access ASUS RT router. It has been tested with firmware version 3.0.0.3134 and 3.0.0.4.372_1363 and 3.0.0.4.376_3754. You can use this application to access your ASUS RT series router over wifi or even over internet (if dynamic DNS is enabled) remotely. If you are sure about FW compatibility of your router with this App then you can run first MyAsus Compatibility Checker (https://itunes.apple.com/us/app/myasus-compatibility-checker/id734258011?ls=1&mt=8) and verify compatibility.
To configure Dynamic DNS (DDNS) see below article:
http://ashishd.wordpress.com/2011/06/27/accessing-you-home-network-over-internet-part-i-without-vpn/