You’re away from the office, and the phone rings: it’s someone who needs a document signed, or perhaps edited, in a matter of minutes. You don’t have time to make it back to your desk, but luckily all the apps you need are available on your smartphone.

It can be impractical to use a small screen to get work done, but sometimes there is no other option. If you’re an on-the-go professional you need your phone to be more than a Facebook machine: it needs to be a pocket office.

Here are five categories of apps you need on your phone to turn it into a productivity powerhouse.

Document conversion

If someone emails you a PDF and you need to make changes it has to be converted. Luckily there are several apps available to choose from. PDF to Word is one example: it can pull from email, Dropbox, and Google Drive, and with just a few taps produces a .DOCX from a PDF.

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There’s an hour wait unless you pay $5.99 for the premium version of the app–not a bad investment if you think you’ll be converting a lot. Other apps are available as well, such as easyPDF (iOS, Android), which can convert both ways.

Document editing

That .DOC file isn’t going to do you a lot of good if you don’t have a word processing app on your phone. There are a lot of these to choose from, like Microsoft Word (iOS, Android), Google Docs (iOS, Android), and Pages (iOS only), to name a few.

Make sure you have a digital signing app installed on your phone too. You might have to just sign a PDF instead of converting it and making edits, which is exactly what DocuSign (iOS, Android) and apps like it are for. You can sign and email documents right from the app.

Cloud storage

We live in a post-desktop era of computing, where most of us know storing documents directly on a computer is a bad idea. That goes double for mobile devices, which are much more likely to vanish than a desktop computer.

Cloud storage is a must for anyone doing work on a mobile device. The most popular are Google Drive (iOS, Android) and Dropbox (iOS, Android), but there are others out there. Make sure whatever documents you’re working on are synced to the cloud in case your phone dies, gets stolen, or breaks.

Business management

Running a business, or your small part of one, doesn’t mean you have to be tethered to a desk anymore. Many of the applications that are used to conduct business have a cloud-based component, which means you can use them wherever you happen to be (it’s up to you whether that’s a good thing or not).

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Platforms like Salesforce have mobile apps for iOS and Android that reportedly feature all the same content as their desktop apps. Several different PM platforms also have mobile apps: Trello (iOS, Android), Asana (iOS, Android), and Basecamp 3 (iOS, Android) all have on-the-go options available.

Communication

There’s more to business communication than sending emails and texts. Sometimes a face-to-face call on Skype (iOS, Android) or quick group conversation in Slack (iOS, Android) is necessary.

If you take a lot of business calls on your personal phone it’s also worth considering using a secondary number, like those provided by Google Voice (iOS, Android) or Citrix Convoi (iOS). You can give your number out to clients or coworkers and never have to worry about getting called on your personal one again.

You can even get an app on your phone so it can send and receive faxes with eFax (iOS, Android). While most of the world has moved on to digital documents there are still some diehard faxers out there–don’t get stuck looking for a FedEx or UPS Store when you can do it all from your smartphone.

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