Why is Instagram so popular?

Instagram helps ordinary people feel like celebrities. The fact that they can have followers & strangers liking their photos, satisfies their Egos and makes them feel important. Instagram gives a self confidence boost to many of it's users .

Facebook is now full of negativity. Instagram provides a safe escape from the negativity on other social networks. Since the worst thing you can see, there is a picture, it's nothing compared to an offensive negative post.

One of the factors that helped Instagram become so popular is that it helps people share their pictures on all other social networks Instantly. Instagram became more of a tool that allows people to edit their pictures before sharing them on their preferred social networks.

Instagram was launched in October 2010. At that time there were very few mobile apps in stores and thus the competition wasn't tough. Yes the product is great but it was also helped by this fact.

The reason you think that some people are showy while others aren't is that every person shows off in his own unique way. In the end we are showy creatures and Instagram helps us do that. Not only can we show our best to friends using Instagram but we can also do that to total strangers.

As a general rule simpler products are much more likely to succeed since humans always choose the easier path over the one with a long learning curve. This is also one of the reasons the iPhone got so popular. (See Why some people think the iPhone is the best phone?)

Some people consider Instagram a more private social network. As a result many people feel comfortable sharing pictures they wouldn’t have felt comfortable sharing on Facebook. (See Why do people share photos on social networks?)

Instagram is more fast-paced than Facebook. A person would rarely take a picture of his food and post it on Facebook, but with Instagram sharing such moments as they occur can be done much faster.

All types of content provoke certain emotions but on Instagram it’s very less likely to find something that makes you mad, extremely annoyed or frustrated. Compare this to Facebook where you can get involved in a serious verbal fight any time.

Pictures are much easier for the brain to process than text. So Instagram puts less load on the brain. Most people don’t know that fact, but they still feel more comfortable using it, because it makes them feel better by putting less of a load on their brains.

Humans like to get involved into activities that resonate with their moods. Because Instagram's environment is clam people feel like using it when they feel calm. It's very likely that you check Instagram as soon as you wake up.

People who don't like the way they look in pictures can use filters to enhance their looks. Because Instagram filters can make people look better many people prefer to post their pictures on Instagram instead of Facebook.

Because Facebook was founded in 2004 the people who use it are relatively older than the people who use Instagram. With the launch of Instagram teens found a social network for young people like them. Some teens preferred it over Facebook as they considered it the social network for grown-ups.

New generations are growing more and more impatient. Because Instagram allows people to take pictures, edit them and post them very fast it caught the attention of the new generation that can't tolerate waiting. 

Because many people don't find it a good thing to have few followers on Instagram compared to their friends and peers they get hooked up to the App and post often with the goal of getting more followers.