Instagram, the mobile photo sharing app, released an Android version earlier this week in an event that I believe has turbocharged the already briskly growing social photo service. New data crunched by Amsterdam-based startup Skylines shows that is exactly what is happened.

Some of that is to be expected – during certain times of the day, Instagram was adding about 2000 new users per minute and added a total of a million new people during the first 24 hours. (Related: Instagram and the Android effect.)

The impact of these new people? Well, Skylines compared the 24 hours prior to the launch of the Android app with the 24 hours following the launch of the app and found that there was a “55 (percent) increase in the amount of pictures posted to Twitter from Instagram.”

Skylines, incidentally, is a service that sifts through various social feeds and is able to identify trends such as what service is being used to share photos on social networks such as Twitter. The number of photos from Instagram that were shared on Twitter went up from almost a million pictures a day to almost 1.5 million pictures over the last day.

On average 20 percent of the pictures (of the services Skylines tracks) are from Instagram, but over the last 24 hours this jumped to 30 percent of all pictures, a sign that Instagram’s Android bet might be paying off handsomely. All other services, besides Twitter’s own service, saw their amount of pics posted shrinking, Skylines pointed out. Instagram is now the largest single client posting pictures to Twitter.

I think if Facebook and Twitter are paying attention, then they should be worried. Why? Because Instagram will soon gain the mass and the momentum to challenge the two. The fact remains that even today, photo sharing is the primary driver of social networking, especially at Facebook.

My colleague, Erica Ogg pointed out to research from 6sight that shows that photo sharing on the smartphones has a long way to go. And that is good news not just for Instagram, but also app makers who want to sell tools and apps for this whole new class of mobile photography.