Fish Friends, a fairly new Playdom game, and Mall World, a well-made fashion game that appears to be by an indie developer called 50 Cubes, top our list of the 20 fastest-growing Facebook apps with fewer than a million users.

We cover the games in depth over at Inside Social Games. Also note on the AppData top 20 list, below, that Facebook hasn’t updated the stats for several of these apps for several days, keeping the reported numbers a bit lower than usual:

	Name	MAU	Gain	Gain, %
1.	Fish Friends	505,480	+232,227	+84.99
2.	Mall World	401,686	+214,043	+114.07
3.	iKarma	440,775	+173,151	+64.70
4.	Akinator	551,225	+130,524	+31.03
5.	Takipçilerim	203,906	+101,557	+99.23
6.	Hızlı Yaz	249,918	+92,731	+58.99
7.	Big Prize Giveaways	249,044	+84,500	+51.35
8.	Premier Football	893,658	+84,178	+10.40
9.	What Song Was #1 on your Birth Date?	760,205	+80,652	+11.87
10.	Car Madness	533,794	+73,880	+16.06
11.	Hugglicious	473,809	+72,496	+18.06
12.	Your Japanese Name	844,296	+70,131	+9.06
13.	Evony	202,660	+68,257	+50.79
14.	Agatha’s Horoscopes	163,936	+67,944	+70.78
15.	武俠風雲	275,226	+65,094	+30.98
16.	Decorative Writing	876,054	+63,702	+7.84
17.	My Tribe	314,296	+60,527	+23.85
18.	Know Your Name	125,205	+59,229	+89.77
19.	FarmVillain	405,014	+56,929	+16.35
20.	Quizazz	786,309	+56,522	+7.74

At number three, iKarma is picking up users with a flashy combined horoscope and luck interface, along with viral sharing aimed at the superstitious — just share this app with your friends, and your luck is bound to improve! Or, at least, your luck as reported by iKarma.

Akinator is a French quiz game, formerly only in that language, though it appears to have expanded into English now. The “Akinator” is a genie that plays a version of 20 questions, although it appears to pre-determine the category you’re guessing in. Following it is Takipçilerim, which is a Turkish-language quiz app, while Hızlı Yaz is also Turkish but appears to be a typing game.

Big Prize Giveaways is exactly what it claims, although what qualifies as “big” is, obviously, in the eye of the beholder. As our regular readers may remember, a similar concept recently helped Marketplace gain millions of users.

Take a look over the rest of the list — there are several more interesting apps that have just begun to grow, including Decorative Writing, which is the calligraphic version of Graffiti, and FarmVillain, an increasingly successful wall-posting parody of FarmVille.