We suggest JioFi is a better option. Because -
01) JioPhone is slightly cheaper than the standard price of JioFi.
02) You cannot make voice calls direct from the JioFi but you can make voice calls direct from JioPhone - either from the Jio sim card or your regular sim card.
03) JioPhone can serve as a perfect standby phone as it has dual sim card slot and a memory card slot also.
04) You can use JioPhone direct to watch youtube videos, listening FM radio while traveling but in case of JioFi direct usage is not possible. You have to connect the JioFi to your main device.
But JioFi has 2700 mAh battery while JioPhone has 2000 mAh battery capacity.
Yes, you can use Airtel sim card in the JioPhone but the Airtel sim card will work only on 2G network.
Yes, JioPhone does have speed dial functionality.
Unlimited. JioPhone comes with 4GB Internal Memory - so, you can store as many contacts as you want, depending on the free memory on the phone.