The JioFi is a portable modem card, Wi-Fi or router where one can carry anywhere you go and surf web, make HD calls, sent SMS and even watch movies on the go with a Reliance Jio sim in it.
One doesn't need to worry about shifting the Jio sim to other 4G mobiles as long as you have subscribed or paid the Jio Prime membership of 99 Rupees along with recharge offer of 303 Rupees.
On the contrary, JioFi is enabled to use or to offer for Jio users who doesn't have 4G enabled devices. With JioFi, one can surf or do anything with thier 3G enabled devices at lightning speed experiences you get in 4G.
You can off course use JioFi with any 3G Or 4G devices or even in PC's and laptop with Wi-Fi connections. One can easily shift to 4G phone without any problem. Now Jio works both in 3G and 4G phones.
Last but not least, you can insert the Jio sim to 4G phone from your JioFi and surf the web without any problem. Make sure your new device has installed Jio app to access and activate the features in your new 4G Device.
Hackers never learns but always wins!