I have a friend I want to run a campaign for online. I'd like to use a virtual table-top (VTT) to facilitate play, but I can't get anything to run on my PC that runs on their Android phone and vice versa. Is there a way they can slave their phone as a client to a maptool thing I set up, or a Roll20 session in progress, or anything else? How can I achieve the same aim as a VTT (i.e. rapid transmission of spatial details, immersive graphical environment) given our technological limitations?
I'm looking to communicate the sort of information I would usually use a battle map for, at the same rate and level of detail as I accomplish via battle map. I'm not interested in using theatre of the mind in this particular case, on account of the lack of tactical detail that results from that method (the player in question is newer and I want to focus on the mechanics of combat as a game in some rules-heavy grid-based system like D&D 5e or 3.5 or Pathfinder or maybe something else similar for this campaign). I don't necessarily need to be using a map; what I'm trying to do is communicate positional information accurately, precisely, and rapidly, and I'm going to need to update that information each round, as people move and things like napalm and spike growth or whatever are added to the map.
My player is fairly visually-oriented and graphics are, in my estimation, far and away the best way to engage them and to communicate important information like tone and setting and culture. I'm already going to be sharing world map images and drawings of import locations and other things I can use drawings for, but I don't need any specialized software for that because simple images can be sent via our IM chat system without problems. It's the interactivity and rapid mutability of battle maps that demands a specialized solution; I'm not going to redraw the battle map from scratch every turn and then post it to chat, for example.
If you need the details of my computer hardware, you can ask in comments and explain why; I don't normally like to post that sort of thing on the internet. I am using Windows 10 and my friend is using whatever the latest version of the Android OS for smartphone is, updating as updates become available.
The game is a solo campaign for one player with me GMing.
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