Several months ago I pulled out the P3 STD to get it ready for a shoot and install any updates.  The first thing I noticed was no image was showing on the mobile device.
Phantom 3 STD
Firmware V1.09.02
DJI Go v3.1.42
SD card: SanDisk Ultra 8gb

Symptoms:
- No Image Transmission with SD card in or Out
- Gimbal Status in DJI Go app indicates "Gimbal Disconnected"
- Remaining SD card Capacity not showing and no option for reformat in DJI app.
- SD card has no succesful install file after running through start up


What works:
- Starts up and runs through system check with no problems
- RC has full control of camera movement and controls
- P3 Gimbal status light Green
- P3 green slow blink, and link button green

What I have tried:
- Tried start up in different areas to ensure it wasn't an interference problem.
- reformated sd card on computer and dropped in firmware v1.09.02.  ** After running the firmware in the P3 I checked the log file on the card and it was not there
- Conducted gimbal calibration from DJI Go app
- Relinked the controller
- unistalled and reistalled app
- tried 3 different mobile devices to run app. Iphone 6, X and Ipad mini.

I ran through this so many times my head hurts so I am sure I missing something. If anyone can give me a direction to go is would be appreciated.

Hi thanks for reaching DJI Forum, apologies for any troubles you had. May I suggest to download the app to an android device. Below are the list of mobile devices you can choose from.

I don't have access to an android device at this time but I will look into that option.   In the meantime I will still try and figure out what happened since I know that all the devices I tried are compatible and prior to updating worked fine. It just doesn't make any sense to me and I like to believe its something simple on my end and not the P3 or mobile devices.

Try unplugging the cable pin on top of gimbal.  Also, check ribbon cable for nicks or broken places, and all connections.

I guess I’m missing something.   OP has IOS devices and DJI mod recommends trying a droid?????  
I have IOS devices, too, and a P3A.  Hope others post their findings here.

May be is the post from the moderator strange ,but i could do all operations and upgrades with an Android device with success.
My flights i have done with both iOS and Android devices..