I prefer use Blockchain than others, just pay 0.1 mBtc for any transfer 
Every wallet is like that. It is the recommended fee. 0.0001BTC/1000 bytes. So if your transaction is greater than 1000 bytes, you will have to pay 0.0002BTC but if you want only to pay 0.0001BTC, you can set a custom fee.
-MZ
But some wallets has fixed amount like bx.in.th and btc-e i have the idea because i used them. They have fixed amount of fess like bx.in has .002 btc and btc-e has .001 regardless how much btc you are sending