Are mobile devices a viable platform/market for "User-Generated Content"-based games?

Question

I intend to do a lot of research into this, but I know this community has a knack for delivering hard-to-find gems of knowledge, so I figured I'd ask here first.

Preamble (My Situation)

I'm currently looking into the viability of becoming an independent games developer by selling games for the mobile platforms (iOS and WP7 in particular). However, as I currently work full-time, all development has to be done in my own time (weekends, after-work, early mornings). Thus, I need to be careful with how I spend my time (I also have a social life to maintain). Basically, if I can release something that makes enough money, relative to my time investment into it, to be able to support myself with, I'll seriously consider taking the plunge.

The Question

One of the ideas I've had is for a game in a similar vein to Little Big Planet or Kodu, where the focus is on user-generated content, with the game itself providing a set of tools, samples and access to a 'market' for user-content.

What I envision is a simple set of drag and drop tools for placing content in levels, customising template assets, etc, and node-based editors for behaviour and logic (Think along the lines of Kismet, for those of you familiar with the Unreal Engine).

As a programmer, I've looked into this enough to know it is possible from a technical standpoint. However, what I need to know is if it is viable in terms of userbase. Is there a market for user-generated content games on the various mobile platforms?

Just to clarify, I'm not asking how to do it, I'm asking if it's worthwhile to do it.

EDIT
To reword the question and make it more answerable (given the lack of existing examples), what are relevant design considerations typically associated with the psychology of the mobile gamer that would influence the success of a game based on user-generated content?

EDIT 2
Microsoft have just released an app for WP7 called TouchDevelop that allows users to write executable scripts using a simplified tile-based interface. It's been downloaded a lot and garnered positive reviews. So, that's as strong of an indicator of community interest as I figure I'm ever going to get.

Answer 1

The better answer I can give you is to do this preliminary steps:

1. Evaluate the offort required to build a prototype.

Your prototype should be playable, limited in space (levels or map size or whatever space-related), in features (non customizable colors or static version of dynamic features). A pro if such a prototype may be evolved into a demo version easely.

2. Evaluate the target.

You have to do this before even try to start a such thing using one of the most valuable things you own: the time.

3. Find a cheap/free pretest comunity.

If you want to make a social game you have to reach a relative consistent number of people who are willing to try your game for free. How to obtain this may vary a lot, generally games are appealing things but your prototype may be less actractive as as it could be. If your target is young enough, you may think to add some educational aspect - even forcing it a bit - and try to propose it as project for a school: you can receive a lot of very valuable feedbacks.

To be honest, "volunteering" something good for children is itself something very rewarding and a good way to spend time. If you can reuse the codebase of an educational project - that you give for free - in a profitable project, you absolutely are on the right track.