On the colored coins systems, there is a decoupling between exchange and settlement. There is no in-built mechanism that will inevitably lead to an exchange of assets as a result of a successful match on whatever exchange platform is used.
The word you're looking for is "modular".
Colored coins are just smart property tokens, that could be used in a wide variety of systems. There's no reason to weld them to a particular settlement system. The best results come from teaching an
existing settlement platform to benefit from the features colored coins provides.
Note that this solution in no way requires anyone to
invest in appcoins, which evaporates the entire
value proposition for appcoins.