Help with flat design icons

I'm trying to do flat design but my designs don't look professional. Here is an example, the top row is my second attempt.

These designs were done in Photoshop CS6. Is this the correct software to create icons? As you can see some of the icons are blurry. Am i doing something wrong in Photoshop or should i be using Illustrator for creating icons? Also any tips on icon design would help, i need to master this for website design. Thx.

See original post by Oveltonx