Hi All:
You may remember me but I raced FF in a Swift DB6 for 10 years before I retired (the first time...).
Anyways, I've recently become an Apex advertiser for an iOS app, DriverMonitor, I originally built for myself in my MX-5 and I've found a few sports racers and open wheel guys finding ways to mount a phone in the cockpit and use the app. Its a glanceable in-car live timing app, mimicking the typical pit board but live updated real time in the car. It's intended to complement your dash that displays information to the driver from within the car with data from outside the car (the live timing of the event you're currently in).
Brad Hayes has been using in the FRP FF1600 series and previously in his SCCA racing in his Pipers (picture below). The app is meant to be uber simple in displaying just the information a driver can consume while in the car at a glance: position in class, time or laps remaining or elapsed, split to leader, split to driver ahead and split to driver behind. The app also displays a session status (green, full course yellow and even if you're on the last lap).
Its available in the Apple AppStore, is on iOS only currently and is free to download/install. It is subscription based as I have monthly feeds to get access to the feeds so need to cover those costs; its cost should be roundoff error to a set of tires for the weekend. For old open wheel buddies, there is a free first weekend trial. Reach back to me for details.
More info on the app is available at my website: https://drivermonitor.app