Microsoft Excel is one of the most powerful tools out there for number-crunching. While there are alternatives to Microsoft's Office suite, you may be comfortable with Word, Excel, and PowerPoint if you've been using them for a long time. Thankfully, you can carry over the same level of comfort when using Office on your smartphone. I recently tried using Microsoft Excel's mobile version since I had to get some work done on the go. I was initially apprehensive, since Excel works best with a keyboard and mouse. However, I was pleasantly surprised at the end of it, since Microsoft has attempted to make Excel quite intuitive on mobile.