According to independent metrics tracking site AppData, the social drawing game reached a high on April 3 with 14.6 million daily active users. Over the course of the month that number dropped to a low of 10.2 million daily active users on April 30.
AppData tracks daily active users based on Facebook logins, which is optional to play Draw Something, so the data is not an exact total for number of users. However, the consistent nature of the decline does illustrate a worrying trend for the game that once topped Apple's app store charts.
The drop in active users comes shortly after Draw Something studio OMGPOP was bought by Zynga for over $200 million (£126 million).
New features such as picture saving and sharing were recently added, but made no noticeable difference in user numbers.
However, the loss of users could also simply be a side effect of the game's runaway success as the fastest-growing mobile game in history, attracting over 50 million total users in its first 50 days. The test for Draw Something's longevity will be how long the downward trend continues, or whether Zynga can update the game with new content to bring users back.
At the time of writing, Draw Something is currently number five on iOS app store's top paid charts and number six on both the top free and top grossing charts.