Question 1

What size is the vesa mount?

Accepted Answer

100mm x 100mm

Question 2

Could this be used on an airplane to watch movies (plugged into your phone) and could 2 sets of earphones plug into it?

Accepted Answer

You question had me curious, so I experimented.  Short answer is yes... with some qualifiers (basically the right connectors and power).

I did a simple test and was able to connect with my phone with a USB-C to USB-C cable and then get audio out with headphones connected to the USB-C OTG or to the 3.5mm jack (but not both at the same time).

It only has one USB-c connector that will work with a headset and only one 3.5mm headphone jack.  As far as I know, the audio will go to one of the connectors (USB-C "OTG", or 3.5mm jack, but not both at the same time.  So, "could 2 sets of earphones plug into it?"  Not literally.  But you could, for example, plug a 3.5mm headphone "Y" cable into the 3.5mm jack and then plug in 2 headphones that have 3.5mm plugs.

The other qualifier is that you need to make sure you have enough power to keep both your phone and the display running.  It does power up just from my Samsung 20 FE (simple USB-C to USB-C cable), but not sure how long the battery would last.  You likely need external power for both the screen and your phone (at least the screen, then your phone should last at least as long as it usually does watching movies on battery).  You would need to plugin the screen to a separate source of power (which it possible with a second, lower, USB-C connector on the left side).  To also power your phone and still be able to have a video output to the screen, you can use something like this (note it has HDMI out and power in [PD Charging] to power the phone)... https://www.amazon.com/dp/B07S8MKJ6Q?ref=ppx_yo2ov_dt_b_product_details&th=1 
With an adapter like above, the cables that come with it, and one more USB-C cable for power to the hub (that is passed to the phone), it all works and stays powered on (assuming you have a power source to plug both the hub/phone USB-C power cable and the screen power cable into with sufficient power output).

I have a nice pic of the example setup but Amazon is stupid and does not have a way to post a pic as part of the answer (but will let you post a vid, go figure).  Hopefully you get the idea from my description.

Question 3

Is there a different mount you recommend for this monitor?

I saw 4 holes in the back and am thinking about paying a small mount?

Accepted Answer

Hello friend
Thank you for your question!
Yes, the holes on the back of the portable monitor can be used to mount to a stand, such as VESA.
However, we do not recommend mounting.
Because our small portable monitors are mainly built to be portable, thin and light, the screws cannot be fully screwed into the back of the monitor.
As a result, the stability of the monitor's connection to the stand may not be fully guaranteed, and if you need to mount it then you need to be careful to prevent the monitor from falling off.
Hope this helps
For more questions about our portable display monitor, please feel free to contact: support@forhelptech.com

Question 4

Can this connect via Bluetooth?

Accepted Answer

No Bluetooth connection, just HDMI or C

ASIN	B0BNWWF32B
Additional Features	Longer Cables（1.5M Mini Hdmi/USB-A Power Cable,1.2M Type-C Full Function）
Aspect Ratio	16:9
Best Sellers Rank	#481 in Electronics ( See Top 100 in Electronics ) #14 in Computer Monitors
Brand	ForHelp
Brightness	300 candela_per_square_meter
Color	15.6"1080p
Compatible Devices	Tablet
Connectivity Technology	HDMI, USB
Contrast Ratio	1000：1
Customer Reviews	4.4 4.4 out of 5 stars (6,107)
Display Resolution Maximum	1920 x 1080
Display Technology	IPS
Display Type	LCD
Hardware Connectivity	HDMI
Included Components	Type-C ports and 1 MINI HDMI port, Thunderbolt 3.0/4.0 or USB 3.1 Type C DP.
Item Dimensions D x W x H	16.9"D x 1.96"W x 11.4"H
Item Weight	1.5 pounds
Manufacturer	ForHelp
Model Name	F156P1
Model Number	F156P1
Mounting Type	Wall Mount
Native Resolution	1920x1080
Number of Component Outputs	3
Picture Quality Enhancement Technology	HDR
Refresh Rate	60 hertz
Resolution	FHD 1080p
Response Time	1 milliseconds
Screen Finish	Matte
Screen Size	15 inches
Shape	Rectangular
Specific Uses For Product	Gaming
Total Number of HDMI Ports	1
Total USB 3.0 Ports	1
Total Usb Ports	2
UPC	797505192162 797505192629
Unit Count	1 Count
Viewing Angle	178 degrees
Warranty Description	2

ForHelp 15.6inch Portable Monitor,1080P USB-C HDMI Second External Monitor for Laptop,PC,Mac Phone,PS,Xbox,Swich,IPS Ultra-Thin Zero Frame Gaming Display/Premium Smart Cover

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