If you wanna control your tablet via android phone, why don't give ''Tablet Remote'' a try in Google Play? But texting function may not be supported.
Just few setup steps and you're free to use
But so far i haven seen kind of free apps which allow phone for texting. :/ The only apps which is chargable($2.99) called ''Tablet Talk''.
"Tablet Talk works by connecting your Android tablet and phone over Bluetooth or WiFi, allowing you to text on your tablet anywhere and anytime. At home? Just connect your tablet and phone to your WiFi network. At work or on the road? Switch to Bluetooth mode and your tablet can SMS without an internet connection.
When you receive a text, it instantly syncs to your tablet. When you send a text from your tablet, it instantly syncs to your phone, where it is sent using your mobile number. Even status updates for sent SMS sync instantly to your tablet.
But what about when you don’t have your tablet? Whenever you connect your devices, Tablet Talk will automatically sync any newly sent and received texts to your tablet, ensuring your tablet’s inbox is always up to date!" from googleplay
Just a suggestion though
Whitefang