My dad has hearing loss and hence needed a phone that
1) works with his hearing aid, so that there is no interference between phone and the hearing aid, both being electronic devices
2) Has a good voice clarity while hearing
3) is less than 10k INR
we went to Univercell mobile store in Indiranagar, Bangalore, where a young chap helped us to try various mobile phones with my dad to check for hearing quality.
We narrowed down to three models, Nokia, Samsung and Sony.
Finally after all tests, we narrowed down to Sony Xperia Tipo, it has Android ICS and had good voice quality while hearing. Now i don't have to shout over the phone to talk to my dad, it is like talking to other ppl over phone and he is able to respond to me over the phone.
Price (as of Apr 10th): 9000 INR
the other models that we tried.
Samsung Galaxy Y Duos (better than Nokia, but Android version was 2.3 and voice clarity was not as good as Sony)
Nokia Asha (bad compared to both Samsung and the winner).