There are all sorts of ways to mount a phone running Mimo onto the Pocket 3 but I've just discovered a small accessory which, for me at least, is the perfect way of getting the job done in simple but effective fashion.

I'm using the "Accsoon Multi-Directional Cold Shoe Adapter".  This screws easily into the tripod thread of the camera (well, the little extension piece or the battery pack) and the way it screws in makes it very easy to get it on straight.  Then, use just about any phone adapter with a cold shoe mount incorporated (most do) that fits on the bottom of the Accsoon adapter, and it can be angled up or down or flat or whatever you want.

What I like about it is that it is light and couldn't be less bulky if it tried.  And I much prefer to have the phone below the camera (instead of to the side) as it balances better, and having the weight of a phone down there can help increase inertia of the hand when walking, thus reducing Z axis movements (bobbing up and down).

I'm hoping to attach a couple of photos...

Now, there's just one caveat - there seems to be more than one version of this accessory.  The version I got from Amazon wasn't as illustrated there - mine has sockets in the side for tiightening the tilt of the accessory (which can be adjusted so that it's tight enough but can still be readily re-angled without needing to use the supplied wrench) and a lever-type thing for tightening the grip to the cold shoe of the phone holder.  That's all ok, but the hitch was that on mine, there was a little pin projecting up beside the tripod screw, intended I think to mate with a socket on another Accsoon accessory, and I had to carefully file that down before it would attach properly to the Pocket 3 base.  But that was a whole lot easier than returning it!  Looking at the many adverts online for this accessory - google for it - some have photos which actually seem to be a mishmash of versions, so even the retailers seem confused.  Also, the price can vary a bit so shop around.  The cheapest I saw was at "Videoguys" in Australia who have it on sale for about 66% off.  (Which version?  I think it's the one with the pin which has to be filed off).
   
Now let's see if I can attach a photo or two, showing mine in use in conjunction with a ScottyMakesStuff case....

https://photos.app.goo.gl/bHCDRuF42r9qESQS8

https://photos.app.goo.gl/mJmzypCFGHtfboQc7

Accsoon Multi-Directional Cold Shoe... (videoguys.com.au)

There are all sorts of ways to mount a phone running Mimo onto the Pocket 3 but I've just discovered a small accessory which, for me at least, is the perfect way of getting the job done in simple but effective fashion.

I'm using the "Accsoon Multi-Directional Cold Shoe Adapter".  This screws easily into the tripod thread of the camera (well, the little extension piece or the battery pack) and the way it screws in makes it very easy to get it on straight.  Then, use just about any phone adapter with a cold shoe mount incorporated (most do) that fits on the bottom of the Accsoon adapter, and it can be angled up or down or flat or whatever you want.

What I like about it is that it is light and couldn't be less bulky if it tried.  And I much prefer to have the phone below the camera (instead of to the side) as it balances better, and having the weight of a phone down there can help increase inertia of the hand when walking, thus reducing Z axis movements (bobbing up and down).

I'm hoping to attach a couple of photos...

Now, there's just one caveat - there seems to be more than one version of this accessory.  The version I got from Amazon wasn't as illustrated there - mine has sockets in the side for tiightening the tilt of the accessory (which can be adjusted so that it's tight enough but can still be readily re-angled without needing to use the supplied wrench) and a lever-type thing for tightening the grip to the cold shoe of the phone holder.  That's all ok, but the hitch was that on mine, there was a little pin projecting up beside the tripod screw, intended I think to mate with a socket on another Accsoon accessory, and I had to carefully file that down before it would attach properly to the Pocket 3 base.  But that was a whole lot easier than returning it!  Looking at the many adverts online for this accessory - google for it - some have photos which actually seem to be a mishmash of versions, so even the retailers seem confused.  Also, the price can vary a bit so shop around.  The cheapest I saw was at "Videoguys" in Australia who have it on sale for about 66% off.  (Which version?  I think it's the one with the pin which has to be filed off).
   
Now let's see if I can attach a photo or two, showing mine in use in conjunction with a ScottyMakesStuff case....

https://photos.app.goo.gl/bHCDRuF42r9qESQS8

https://photos.app.goo.gl/mJmzypCFGHtfboQc7

Accsoon Multi-Directional Cold Shoe... (videoguys.com.au)