In version 2.8.0 of OBD Fusion for iOS, we have greatly improved backgrounding support. When using the Automatic Car Adapter or a compatible Bluetooth LE scan tool (e.g. LELink, Carista, etc.), OBD Fusion will remain connected even if no longer running in the foreground. This can be useful if you switch applications to get turn-by-turn directions, use a music app, take a phone call, or turn your screen off.
After initiating a connection - either manually or using the automatic connection feature - OBD Fusion can enter the background while continuing to calculate trips statistics (such as vehicle fuel economy and mileage) and log user-configured vehicle parameters (including GPS data) to file if data logging is enabled from within the app settings. Enable notifications for OBD Fusion in the iOS Settings app if you wish to be alerted if the app is disconnected from the vehicle when running in the background.
Background Support for Wi-Fi Scan Tools
iOS limits the types of activities that can be performed and communication types that can be used when an app is not running in the foreground. OBD Fusion will continue to run in the background with Wi-Fi scan tools, but because of iOS restrictions, this is limited to a short duration.