There are hundreds of thousands of apps and millions of websites today. In this increasingly competitive world it is more important than ever to differentiate your startup from others, so that it can stand out. Getting attention is one of the hardest things to do and you will not get it with another copycat app. You must innovate on an idea and put your own spin on it to be noticed. Here are some examples of companies that have done this extremely well:
Path – only 150 friends and strong on mobile

While on Facebook users can add up to 5,000 friends, Path draws a line on how many friends you can have to give users a more intimate experience. Path also started only on mobile, so they have a much better user experience on mobile than Facebook.
Zappos - customer service

Zappos distinguished itself almost solely by their amazing customer service. Zappos initially didn’t spend any money on advertising, but instead put that money into improving it’s customer service.
Plenty of Fish (POF) - free

PlentyofFish is free with ads, while most other dating services are paid, including it’s biggest competitor Match.
Walmart – low prices

Walmart spends less on everything else to make sure they always have the lowest prices.
Fox News – conservative news

When Fox News was launched in 1996 all other news stations had a liberal bias. Fox differentiated itself by being the only conservative news station. Fox is now the most profitable news station by far in the United States, but it should not come as that much of a surprise. ABC, NBC, CNN, MSNBC, etc. are all competing for the liberal and moderate audience, while Fox has a monopoly on the conservative audience.
Google Chrome - clean, simple, and fast

Internet Explorer is very clunky and slow, which lead many users to Firefox. People then left Firefox after it became slow and clunky as well. Chrome came in and has steadily gained market share because it is by far the fastest browser and because it is clean and simple. Pretty much the complete opposite of Internet Explorer.
Instagram – free and fast photo uploading

Instagram was launched after similar photo filter app Hipstamatic. The difference however was that Instagram was free, which let it grow much larger. Also, Instagram is much faster at uploading photos than Hipstamatic.
Facebook – clean white background and users have to use real name

Myspace was founded before Facebook, but Facebook made itself obviously different from Myspace. Facebook had a clean white background, while Myspace let users customize it. Myspace embraced fake user profiles, while Facebook wanted everyone to use their real name. Facebook was only allowed at prestigious colleges in the beginning, while Myspace had a more libertine feel to it. Facebook made sure to draw a stark contrast between it’s competitor, so that it would stand out.