The simplest solution would be to contact your Provider and ask about a "Partner or Flexi Card" this is basically a Second SIM as a Micro Card which you simply insert into your Tab and it has the SAME TelNr. as your First SIM....This is convienient because once you Insert and Activate these Second SIM's you forget about it.
Your Original SIM becomes the Master SIM and the Second one becomes your Slave SIM so too speak..once it has been Activated by your Provider YOU can choose which SIM becomes Master or Slave by inserting a simple code, when you receive Calls or Messages your Master SIM rings and if you DO NOT pick up after several Seconds it Transfers automically to your second Slave SIM and this then rings..!
I have this solution it saves clogging up your Tab or Phone with junk Apps and works perfectly.!!!
Check with your Provider about Terms, Costs and Conditions.
Cheers and Enjoy
Andrew