Beleive it or not, my biggest strategy for not only saving power but for ensuring it remains on has nothing to do with Infinite Flight or the settings of the device relating to the performance of infinite flight Itself!
My strategy is turning on Guided Access, a system on IOS that is geared towards putting more short-term restrictions on your device. I make sure that the settings on this show that all possible device inputs are ignored by the device during the flight: All buttons, touches, movements, you name it; will have zero impact on my flight! It’s amazing! The most common time I’ll use this is when flying a night flight and I’m worried somebody will wake up before me and conflict with something regarding my flight (most of the time by accident), or when I am very active and about with my device near me, and I’m protecting against any unwanted movements of my phone, buttons being pressed, etc (which could result in the flight being affected). This also saves power because since my device gets locked on lowest brightness, even the smartest hacker in the world wouldn’t be able to crack my whopping twelve digit passcode to change the brightness levels or settings.