UPDATE: And it turns out that price drop was only due to a temporary glitch on Google Play, and the games' prices are - sadly - back to normal.
That is good news for those who love the endless running genre in Temple Run or the puzzles and logic required in the other games.
Moreover, these games will from now on remain free - that is not a limited-time deal. Google Play’s policy is that once an app goes free it cannot go back to being paid. You can find the links for the games on Google Play right below:
source: Android Guys