Record for an hour using mobile phone I want to record someone speaking for about an hour without any gaps. To do this i'm using a Samsung Galaxy s8. 

The default video application splits the video into 4gb files when recording longer videos; which would be ok,  but when I take them into a video editor to join them,  they don't fully match up.

Is there a way round this without rooting my phone. 

I've tried a few video applications and recorded to the internal and sd memories.
Open Camera is an open source app that let's you do this. You can configure it for various times including unlimited.

Android has typically a 4GB limit on video size. Your one hour video will most likely exceed this limit 
. Open Camera let's you restart the video automatically after the 4 GB limit is reached which can be joined in a video editor