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.
No. JioPhone does not have the notification light.
Yes, you can connect the JioPhone with computer.You can also charge it via computer.
Yes, JioPhone does support Live TV. You just need to select the channel, which you want to watch and hit the button "play".