Previously on this forum the moderators have stated that it is only for Debian-related discussion, so I find it surprising that this kind of discussion is permitted here, and I seriously doubt that this is the best place. There just isn't that much expertise and many users have quite negative additudes (rightly so!) towards android and "mobile devices". Maybe you should ask in an android forum?
satimis wrote:I have 2 Samsung mobile phones, one with a SIM card to connect Internet and another one without. I tried the 1st one and it worked but the 2nd one didn't. (my spare phone)
I don't understand how you tried one wihout the other, when you were describing using them together to form the network?
I'm exploring phone-to-phone direct connection via WiFi or Bluetooth without additional device.
Look up the bluetooth spec and realize that this is essentially impossible. Also, the link you post is close to a decade old and Android has had quite a number of new versions since. You should be more critical when reading random opinions online.
CwF wrote:I'm a little surprised 'they' haven't come up with a virtual modem program for packaging data for use over a 'voice' connection.
not sure whether this is relevant here, as the OP wants to not have sim card, which would exclude GSM also.
satimis wrote:No, each time TeamViewer will provide an IP address for users to login and connect the remote phone. Therefore Internet access is a MUST
This sentence makes no sense to me. Are you maybe confusing networks and internet and some how thinking that an IP-address is only possible when you have internet access?
On my searching, I haven't discovered an app working phone-to-phone.
There probably are few people that would want to do this. Android phones are used by the majority for other kinds of things. A very small minority wants to remote control a smart phone. Those that do, either have internet or a LAN. How many users can there exist that want to remote control a smart phone without internet? So, no ready-made solution is likely, you're going to have to hack.
Actually, it is quite hard to understand why you want to do this. Let's start with the fact that you say that you want to remote control a phone that is a few feet away? So, if I am understanding it, you want to be able to use the touch display as a user interface on phone A to control phone B, which is a few feet away to take photos. Why?
Consider also that you do not need wireless for such a short distance. You could just use a USB-mouse for the control part. Then you would only need to send the contents of the screen from one phone to another, and not need a full remote user session. This would be significantly easier. You could even probably use a physical mirror to cast the screen of the first phone and activate the shutter using a USB mouse. Low tech solution. IF that is what you want