Asked — Edited

Can We Use The ARC Mobile App Outside Our Home Network?

Hi, I am trying to use the ARC mobile app to control my EZ-B v4 using  4G network on my android phone using port forwarding. Have been trying but with no success. Is this possible? Any help would be great. Thx

Related Hardware EZ-B v4
Related Control Interface Builder


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You don't need any internet to control EZBv4 if you use the built in Adhoc wifi server that it has ,you just need to change that setting at the EZ B server address and it will connect to your cell phone or laptop with no other wifi needed.


Thanks, but did u read my question?


@proteusy: Can you confirm:

  1. Android Phone with Hotspot activated  ?
  2. EZ-B client mode connected to the Hotspot network ?
  3. Where is ARC connected ?

Olá ptp,

  1. Android phone will be using 4G network so i can control the EZB-4 even if i am not home.
  2. My EZB is in client mode
  3. Would use the mobile app to control the robot. All i would like to do is control the robot form anywhere in the world using ezb mobile app. Cumps.
#5   — Edited

@proteusy Sorry the delay, travelling limited access to the PC.

ASFAIK It's not possible to use to use a 3G/4G Modem or mobile phone as NAT server (port forwards), I don't know if is by default but in most scenarios the 3G/4G get's a private IP from the mobile provider then the IP is masqueraded (NAT) with a public IP.  When you access a public site the public IP you see is the mobile operator endpoint.

IPv4 range is saturated is almost impossible to serve a public Ipv4 to all mobile devices.

User-inserted image

As you can see above my mobile phone is connected to 4G network and the cellular IP is a private class A (10.x.x.x) so when you do NAT you are masquerading your internal IPs (mobile hotspot) with the and that IP is masqueraded again (by the mobile provider) to the

You can get out but you can't get in although is possible to configure VPN client site-to-master site but that is a different scenario.


I think PTP may be overthinking this.  Will the robot be on your home network or with you where your phone is?

I too am traveling, but this weekend I can provide detailed instructions and ideas for either situation.



Hi thetechguru, the robot is connected to my home network. The idea is to make a telepresence robot that can be accessed from outside my home network using my phone.


Ok.  Fairly easy, although if you can have a home PC on as well, it is even easier.  Biggest issue without a PC is knowing the current public IP address of your home network.

I'll write up something this weekend.   There are several conversations about this going back several years on the forum, but digging through all of them for the right answer may be more trouble than it is worth.


Not overthinking, misunderstanding.

I assumed the EZ-B/Robot is behind a 3G/4G network, before i used an Android phone to share the internet (hotspot) currently i use this:

User-inserted image

The facts above post 5 are correct if you try to configure a 3G/4G device as NAT server.

There are a few threads discussing the common scenario (cable internet providers), check one of my posts: post #4 https://synthiam.com/Community/Questions/Connect-To-My-Cloud-And-Use-The-Virtual-Machine-4902

I don't know why I assumed the most complicated scenario ...

I would wait for a good post from thetechguru:)


PTP's link above is exactly what I was going to provide as method 1.  It is probably the simplest, but you do need a dynamic DNS service, or some kind of device on your network that can send you your IP address periodically (your IP is likely to change any time your router reboots, and with some providers more often).  It is fairly easy to script in windows or Linux (on a Pi) to send you your current IP address by email or text periodically so you don't need dynamic DNS.

Method 2 would still require needing to know your IP address or a dynamic dns host name, but would be a bit more secure.  Set up OpenVPN on a Raspberry PI on your network.  You can then connect to it from your phone, and your phone appears to be on your network for all intents and purposes.  This is a bit more secure (if configured correctly) because you only have one port forwarded, and OpenVPN is very secure.

Method 3 would be to have a PC on your network running and use TeamViewer (or similar) remote software.  The advantages are you don't need to know your IP address because the connection is controlled through the service provider, and you get the full power of ARC rather than the more limited mobile interface.  Disadvantage is that you are seeing the entire ARC screen on your phone, and even though you can zoom in and pan around, it might be overkill for your purposes.

Method 4 would be to use the web server or custom web server in ARC to create a custom remote interface.  Not much benefit to that over the other methods though (and in fact, the standard web server does not even have a password, so probably not a great solution).

This weekend I'll provide more details on each of these with some links and maybe even some diagrams if I get inspired:)



As usual, my weekend had more things to do than time to do them.  I'll try and update more details on these solutions one evening this week.


Thanks Alan, i am using team builder and it is ok.



i am using team builder and it is ok.
That is actually my preferred method despite the density of data on the screen.