I'm hoping to produce an amateur movie.

I may be renting some equipment: (professional camera, microphone and digital recorder) but I hope to primarily use my own equipment: camera phones, professional microphones, analogue audio mixer, audio digitizer and a laptop. I hope to produce the video on an open-source video editor (Linux or Windows).

In case it needs to be said, I'm on a near-zero budget! The biggest concern I have is how I will synchronize a phone camera with an external microphone fed into the laptop.

Are there any techniques to help with this? I had a go before and it's surprisingly hard getting the audio perfectly sync'd with the video. Are there any tricks?

Also, what industry-standard technologies are used for synchronizing professional microphone setups with video, and between multiple cameras? I assume there are at least a couple of old analogue and newer modern digital methods?

Thanks!

Edit: I looked at this link but it didn't go into detail or explain different options.