Editors' note, October 23, 2014: This review was updated with new information from the latest update.
Apple's Numbers (iOS|Mac) is useful for creating spreadsheets and organizing data while away from your desktop. Now, with iOS 8 and Yosemite available, it gets even more, with Handoff features and the added ability to use AirDrop between iOS devices and Macs.
Still, Numbers is not going to take the place of more robust spreadsheet apps like Microsoft Excel, but it's great for tinkering with your data on the go and especially good for bringing in graphics to illustrate your data. On the iPhone the app works admirably, but the smaller screen size makes a little less easy than the iPad version, unless you have the iPhone 6 Plus.
Like the other iWork apps, Numbers was built from the ground up last year for both iOS and Mac, with the iOS version seeing improvements, while the Mac version has lost some features to give both a level playing field. Due to a backlash of user complaints about the Mac versions Apple has since added features to both versions, but still lacks features found in Numbers from iWork '09.
It's also important to note that, like my reviews for Pages and Keynote , I did most of my testing on the iPad. You don't lose functionality when moving from the iPad to the iPhone, and it will come in handy in a pinch, but using it on the iPad is a much better experience. So, whether you should download the app depends on the device. The experience on iOS is better than before, but you might want to wait on your Mac until Apple adds more features.
Learning the ropes
The app comes with a Getting Started screen that gives you the basics before you open a spreadsheet, but once in the app, Numbers walks you through everything from basic spreadsheet use to more-complicated charts and graphs using an intuitive tabbed interface. As you learn the various features in the demo templates, you can try them on your own as you go -- an excellent way to learn the ins and outs of Numbers.
You get over 30 Apple-designed templates, a freeform canvas for tables, interactive charts and more than 250 spreadsheet functions. When you double tap an individual cell, Numbers for iOS also uses what Apple calls a Smart Keyboard that gives you the best set of tools for the type of data you're working with. iPhone and iPod Touch users will appreciate the Smart Zoom feature, which automatically zooms in on the part of the spreadsheet you're working with, but it will still feel crowded as I mentioned above.
The touch interface makes interacting with spreadsheets easy. You can add rows or columns by grabbing onto the handle at the end of a row and drag it to the desired number of rows. Selecting multiple fields requires you tap and hold, then drag to select as many fields as you want. Once selected, you can tap and hold, then drag to move the selected fields to another area.
When entering data Numbers detects the type of content you need and gives you an interface that's most suitable for that type of content (fields with calculations get a calculator and a formula selector, for example). So with a touch of your finger you can organize, move, and smartly edit or change your content, all without the use of a keyboard.
It's also easy to make charts. If you have a finished spreadsheet, or even if you just want to make a column, bar, or pie chart using data from a portion of your spreadsheet, Numbers requires only a few touches. Use the plus-sign button in the top right, select the type of chart you want to display, then drop the chart into your document. From there, you can tap on the chart, resize it using anchors, then touch the paintbrush at the top to change the chart type and color to display your content the way you want.
There are also a handful of 3D charts you can use and you can rotate them to fit the look you want once they are on screen.
Collaboration and iCloud Drive
Collaboration features are something that's been around a long time in other office suites like Microsoft Office and Google Docs, but iWork made them a part of all the apps when they released last year. With all three iWork apps, you can invite up to 20 people to work on the same document simultaneously and you'll see other users interacting with the document in real time. The app color codes each user so you know who is working on a particular section. People also can make comments on sections, which then show up for all people sharing the document. These are things that other productivity software already does, but it's nice to see it added for Apple devices.