According to one mobile app metrics firm, Instagram appears to be suffering in the wake of its recent terms of service debacle. AppData tracks the number of daily, weekly, and monthly users of apps that can connect to Facebook, and its recent daily data shows a 25 percent decline in daily users of Instagram over the last seven days — previous daily usage counts were nearly 16 million, while the most recent data now shows daily users sitting at about 12.4 million.

AppData was quick to attribute this to Instagram's revised terms of service, which were announced on December 17th and immediately trigged a rather misinformed backlash against the company. The company quickly changed course and returned the TOS to its original state, but AppData apparently believes the outraged userbase started dropping the service, leading to the decline in its data. The analytics firm told The New York Post that it was "pretty sure the decline in Instagram users was due to the terms of service announcement."

It's too easy to assume Instagram's terms of service update is behind this change

While that's certainly one possibility, it's far from the only one. AppData's measurement only shows that there was a decline in users who have Instagram connected to Facebook — while there's no doubt that represents a sizable and likely representative portion of Instagram users, it isn't the entire Instagram userbase. The decline could come from users unlinking their Facebook accounts; those users could still be using Instagram, but AppData wouldn't have any visibility into that. There's also a question of timing — by December 25th, Instagram had already reversed course on its decision, making the decline oddly timed if it is indeed related to the initial burst of outrage.

Furthermore, more of AppData's own metrics cast some doubt on this conclusion. While daily users did indeed drop on December 25th, weekly and monthly user counts are right in line with previous timeframes. (Weekly user data counts the previous seven-day period up to today, while monthly counts the previous 30 days up to today.) In fact, weekly users are up 2.3 million over the last seven days, while there are 1.7 million more monthly users, as well. Instagram was also far from the only service to suffer a drop in users right around Christmas, according to AppData. The Next Web found that a host of other apps, including Pinterest, Spotify, and Farmville, suffered notable AppData declines right in the same time period as Instagram

AppData's metrics may show that something drove some Facebook-connected Instagram users away from the service, but there's not enough data to conclusively show that Instagram's terms of service misstep was a contributing factor. Regardless of the reason, we've reached out to Instagram for comment.

Update: An Instagram spokesperson reached out to let us know that AppData's measurement is not reflective of Instagram's true trend. "This data is inaccurate. We continue to see strong and steady growth in both registered and active users of Instagram."

Update 2: AppData appears to be doing some damage control — we just received a statement in which the company claims its statement to The New York Post was "not approved for citation by AppData." It's now saying that the decline is "likely related to the holiday," rather than the Instagram terms of service update. The full statement is below.

AppData reflects only Facebook-connected users of the Instagram app. Though the terms of service change spurred a lot of negative media attention and complaints from users, the decline in Facebook-connected daily active users began closer to Christmas, not immediately after the proposed policy changes. The drop between Dec. 24 and 25 seems likely to be related to the holiday, during which time people are traveling and otherwise have different routines than usual. A number of other apps saw similar trends, including Skype, Pandora, Pinterest and Yelp. The original statement issued by the NY Post was not approved for citation by AppData.