I see some old discussions on this topic, but having just gotten my Spark a week ago and bought a OTG micro USB to USB C cable specifically labeled for Spark, I've followed all sorts of instructions and still can't get the cable to maintain connectivity and allow me to fly.
I've also made sure (unlike others) that the Wifi on my Android (OnePlus 3T running Oreo) is OFF so I can be sure it's the cable that's doing the communication and not the WiFi.

I am running the latest DJI Go 4 4.3.8

Anyone got it working?   Any particular sequence of steps to get it working?

By the way, this works with my Samsung Galaxy Tab S3, but not OnePlus 3T.

Everything is working allright here.. latest software on Note8 Oreo.
You know that OTG connection/cable is directional?
I do not kill wifi, nor do I activate airplane modus on my device... Still connects over OTG every time.

Haggi Posted at 1-5 07:29
Everything is working allright here.. latest software on Note8 Oreo.
You know that OTG connection/cable is directional?
I do not kill wifi, nor do I activate airplane modus on my device... Still connects over OTG every time.

What do you do to be sure it's communicating over OTG and not Wifi?

djiuser_KYwxXolmqeoQ Posted at 1-5 07:47
What do you do to be sure it's communicating over OTG and not Wifi?

This is the sequence I use... every single time!

1. Turn on Remote Control (RC). Wait for solid red.
2. Plug in OTG cable in phone.
3. Plug other end in RC.
4. Choose DJI GO 4 app in popup window.
5. Wait until GO 4 app is open and it says "RC Connected" in lower left corner.
6. Power up your Spark. Try to place RC as close to Spark as possible. (DJI recommend 20 cm)
7. Bonding between RC and Spark should take less than 30 sec.
8. Hit GO FLY!

Try the first couple of times with WIFI off on your device, then you'll be sure its working for you.

Hi there, thank you for reaching out and we're sorry to hear about the trouble, with regards to that you mean when using the OTG connection it seems both device and remote not communicating to each other? For the Reason, OTG connection and Smartphone should work the issue must be the OTG cable then.

Is the phone charging?
Try an older app, you dont need the latest for the Spark

DJI Gamora Posted at 1-5 09:07
Hi there, thank you for reaching out and we're sorry to hear about the trouble, with regards to that you mean when using the OTG connection it seems both device and remote not communicating to each other? For the Reason, OTG connection and Smartphone should work the issue must be the OTG cable then.

It works with my Samsung but not my OnePlus (using same cable) so the problem is probably not the cable.  The OnePlus is close to stock Android so I don't know what else I can try to get it working.   Thanks for the reply though.

Haggi Posted at 1-5 07:58
This is the sequence I use... every single time!

1. Turn on Remote Control (RC). Wait for solid red.

Thanks.  Your instructions worked well for the Samsung Tab S3.  Still doesn't work with OnePlus.

djiuser_KYwxXolmqeoQ Posted at 1-5 13:19
Thanks.  Your instructions worked well for the Samsung Tab S3.  Still doesn't work with OnePlus.

Maybe this will do the trick..

Haggi Posted at 1-5 13:38
Maybe this will do the trick..

https://youtu.be/hBUeSdo38YQ

Thanks, that was the closest bit of advices as I didn't know the OnePlus has OTG disabled by default.  The latest Oxygen OS for OnePlus has a OTG on/off toggle, but unfortunately even with it toggled on it still doesn't let me fly the drone.  I get the "RC Connected" green light on the DIJ Go app, but never the "GO FLY" button.

Haggi Posted at 1-5 13:38
Maybe this will do the trick..

https://youtu.be/hBUeSdo38YQ

Thanks, that was the closest bit of advices as I didn't know the OnePlus has OTG disabled by default.  The latest Oxygen OS for OnePlus has a OTG on/off toggle, but unfortunately even with it toggled on it still doesn't let me fly the drone.  I get the "RC Connected" green light on the DIJ Go app, but never the "GO FLY" button.

djiuser_KYwxXolmqeoQ Posted at 1-5 18:31
Thanks, that was the closest bit of advices as I didn't know the OnePlus has OTG disabled by default.  The latest Oxygen OS for OnePlus has a OTG on/off toggle, but unfortunately even with it toggled on it still doesn't let me fly the drone.  I get the "RC Connected" green light on the DIJ Go app, but never the "GO FLY" button.

Do not give up, bring rc close to drone (20 cm) and wait for the pairing. Maybe a minute.
Green rc connected means otg cable work.

Haggi Posted at 1-6 03:21
Do not give up, bring rc close to drone (20 cm) and wait for the pairing. Maybe a minute.
Green rc connected means otg cable work.

Interesting how differently people use OTG.  My sequence is:

1. Start Spark
2. Start RC
3. Wait for connection - not long
4. Once green on RC plug in OTG
5. GO FLY

works every time.   I do normally put my phone into aircraft mode especially if flying around built up areas.

Yes, I used this setup since last August. The start sequence can be important! This works for me:
1- AC
2- RC with OTG side of micro USB, wait for green led,
3- connect other end of cable to Android phone or tablet,
4- power device. start DJI GO4

I have the galaxy s8 plus and it only works when done as explained in post 14 and 15.