IPO snapshot: Facebook’s top 25 apps by size

Facebook began public trading today at $38 a share and a valuation of $104 billion. These are the top 25 apps on the social network the day of its initial public offering, as tracked by our AppData traffic monitoring service.

We’ll start with daily active users, which is a measure of the most engaged portion of an app’s audience. Note that of these apps, nine are Facebook canvas games. The others are mobile apps, web integrations, desktop apps or a combination. For example, Words With Friends is a canvas and mobile game, Spotify is a desktop and mobile app, and Socialcam has a mobile app, website and canvas presence. The top app, Microsoft, is a web utility that connects Windows Live to a user’s Facebook account.

1. Microsoft12,100,000
2. Draw Something9,100,000
3. Texas HoldEm Poker7,100,000
4. Words With Friends7,100,000
5. Bubble Witch Saga6,400,000
6. HTC Sense5,900,000
7. CityVille5,600,000
8. CastleVille5,200,000
9. Yahoo!5,200,000
10. Spotify5,000,000
11. Astrology4,900,000
12. Hidden Chronicles4,700,000
13. Yahoo! Social Bar4,700,000
14. schoolFeed4,600,000
15. FarmVille4,500,000
16. Diamond Dash4,300,000
17. Socialcam4,200,000
18. Zynga Slingo4,200,000
19. Bing4,000,000
20. Samsung Mobile3,700,000
21. DROID3,500,000
22. Tetris Battle3,500,000
23. Photo Love3,300,000
24. Bejeweled Blitz3,200,000
25. Daily Horoscope3,100,000

Next, we present the top 25 Facebook applications in size by monthly active users. This is a measure of an app’s overall reach. By launching Open Graph integrations, many of these apps have rapidly climbed our rankings in the past months, and drawn excessive media attention whenever traffic plateaued or decreased. Of these apps, nine are Facebook canvas games — and they’re not all the same games that appeared in the top 25 DAU list above.

1. Socialcam51,500,000
2. Yahoo! Social Bar39,500,000
3. CityVille36,900,000
4. Viddy36,900,000
5. Texas HoldEm Poker35,000,000
6. Draw Something30,600,000
7. Static HTML: iframe tabs29,700,000
8. MyCalendar – Birthdays29,000,000
9. Bing25,700,000
10. Microsoft22,800,000
11. FarmVille22,400,000
12. Scribd22,200,000
13. CastleVille22,100,000
14. Hidden Chronicles21,800,000
15. Angry Birds21,400,000
16. Bubble Witch Saga21,200,000
17. Spotify19,700,000
18. TripAdvisor™19,300,000
19. Diamond Dash18,900,000
20. Samsung Mobile18,700,000
21. Static Iframe Tab18,500,000
22. Metacafe17,900,000
23. Words With Friends17,600,000
24. Instagram16,700,000
25. Tetris Battle15,800,000

Be sure to catch up on Inside Facebook’s IPO coverage and stick with us to see how the app ecosystem evolves with the social network’s new status as a public company.