Anyone knows how to flash-fill a portrait picture taken with back-light afternoon sun using an Android and/or iPhone?
The flash used for this (to be purchased) is a Sony mount Godox v350s. This will be done during travels so minimal gear is required.
Just some scrappy thoughts, from half-remembered old considerations of the topic... I hope others can advise you better...
I think you need bluetooth communication for this to function. Because you need some way for the phone to send a flash trigger command. Godox has a phone app that can trigger flashes but it needs that communication with your hardware.
There was a special version of the Godox XPro wireless flash trigger that was sold in America only by a major store (Adorama?) in recent years - the "R2 Pro Mark II"? - unlike the normal XPro, it had Bluetooth.
Godox have recently announced a version II of their XPro trigger, that seems to make that unofficial America-only sequel to the XPro into an official, international version. And it has Bluetooth. But it's only just been announced and you might not be able to buy one yet.
There are probably other options. I'm sorry for the vagueness. Hope this gets you looking in the right directions. I think you do need an extra device of some kind, such as those mentioned above, to be the bluetooth communication bridge between phone and flash.
EDIT: I had a foggy old memory of something... here it was. The Godox A1. Maybe look into it.
The Godox a1 device was discontinued years ago. The current X2 trigger is bluetooth compatible but I don't see a way to sync it with the phone's camera. It just controls the lights remotely to adjust power and grouping. Even that is a kluge that I could not get to work reliably.
I once tried to trigger some godox flashes via their built in optical slaves using a phone flash. Nothing happened. I don't think a typical phone "flash" is intense enough to trigger anything. A phone is really using a long pulse LED.
Even if you could find a way to sync with your phone, the slow required shutter speed and fixed aperture would make finding a correct exposure and flash power combo near impossible.
