rdaneel
Illuminator
Yes, I've tried using this forum on a phone browser, it sort of works, but it's extremely cumbersome and nowhere near as good as using Tapatalk.In practice nothing, but some people prefer using the Tapatalk client to the regular web interface since it's often easier to use and read. Especially if the forum doesn't have a custom mobile skin installed.
I do wonder though, if there is any possibility that the upgraded forum software will have features that might improve it's presentation on phones and tablets, making 3rd party software less necessary. While I like Tapatalk, I expect that it's going to become more common for potential "New Blood" to come to the new forum through searches on their devices, and being told they need to download an app to read the forum properly could be a stumbling block.