iWifi is a free iPhone application developed by Xiaoyan Huang that allows users to test the speed of their internet connection, including download, upload, and ping. The app also provides a graph that shows the consistency of the connection and the Wi-Fi signal strength. Additionally, users can record the results of each test and scan for LAN devices. The app includes a Wi-Fi security check and provides security protection, including ad-block and Wi-Fi protection.

The app also offers an AR speed test feature which allows users to measure the Wi-Fi signal strength in a room. Users can unlock VIP features such as unlimited tests, more accuracy, and no ads through a one-time purchase or monthly/yearly subscription. All purchases are tied to the user's iTunes account.

Users can manage and cancel subscriptions through their App Store account settings. The app's terms of use and privacy policy can be found on the developer's website. Overall, iWifi is a useful app for those looking to test and improve their internet connection speed and security.