I'm personally a bit reluctant to look at my personal credit cards as funding source, especially for a highly competitive venture like a video game.

I personally had a hard time finding the game on the iTunes store. There's next to no press coverage or google hits for it. That's the lowest hanging fruit to generate awareness and interest.

You have 5 reviews with a respectable 3 1/2 (out of 5) stars. One strategy I've used successfully is to create a champion team or early adopters (which is difficult once the game is already launched) and asked them to review the game honestly for either a free copy (if paid) or fully unlocked (if F2P) as yours. You're not telling them you require positive reviews, but most people that take you up on this will be positive. The game, of course, has to stand on its own.

Once you generate both positive press interest and coverage (write every major blogger that covers mobile games and soft sell them on taking a look at the game or hire a PR freelancer that can do this for you) and positive reviews (which may also move you onto "what's hot" and "editor's choice" iTunes Store categories) you have a much better pitch for potential investors.

However, first question they will ask is how the game is selling or, in this case, how the monetization is going since it's F2P. Hope that helps.

This may also be of help: http://www.slideshare.net/tomaso67/wp-mobile-games-marketing