Hello,
  I'm looking for a good way to make payments between mobile phones.
I have tried BitcoinTrader for iPhone and BitPay for Android.
They are nice app.

However they cannot pay to each other because they use different format qrcodes.
I'd like to suggest both developers to use a common qrcode protocol.
For example BitcoinTrader could decode the qrcode from BitPay that, in addition to the address, contains after a question mark also the amount and transaction comment.
An alternative would be to just ignore whatever is beyond the "?" but understand the bitcoin address before the "?".
This would allow payments to go through.

I'd like to post this suggestion here: https://bitcointalk.org/index.php?topic=32168.0.
It is in this new topic while I wait to be allowed to reply outside the newbie area.

Cheers