I do not know about other company app. If u want a best plan on airtel then My AIRTEL APP is the best place.
Other app like paytm, freecharge, mobiwik have no offer for Airtel. If u recharge through Airtel app then u will got extra benifits with this cost and u have a airtel money then 5% extra cashback.
Some recharges only for this app only you can’t find it otherwhere.
Family share, recharge to other network is also possible. So that it is good and it is very easy to use.