By default, you can change your phone’s screen timeout settings from the display settings to keep the screen on.

On devices that don’t have this option, or for users who want a simple toggle, Screen Awake is an excellent third-party app.

For users who want the feature to work for specific apps, Wakey’s paid version offers that feature, alongside other added benefits.

Screen Awake

Wakey keeps whitelisted apps awake - $0.99 upgrade

Caffeine Offers infinite option from system tray