Your phone may be good, but has been stated many times before, your phone is not certified to withstand the G's or the temperatures and pressures that a CVR is expected to withstand.
I think one way or another, the outcome of this will be that the powers that be will come up with some way to more definitely track airliners. Yes, it may involve more significant costs - but when you look at what this search has already cost, and what it's likely to cost in the future - some sort of GPS tracking device is going to be a bargain.