PDF Expert - A great way to unzip files on your iPhone

Discovering the hidden surprises on premium apps

One of the most annoying aspects iPhone and iPad users face is managing .zip files. It's not strange to receive some email attachment that has been compressed just to realise your phone is not capable of opening it unless it's unzipped first.


We've had a look at some ways to workaround this issue installing apps like GoodReader, iFiles or CloudReaders. More recently, I have started using PDF Expert by Readdle — a heavyweight PDF annotation and document reader. Perhaps you also gave it a try a couple of months ago, when it went free as part of an App Store promotion.

Assuming many have installed it already gives me the perfect excuse to show some very useful and somehow hidden functionality in this app.

Direct integration with iOS to unzip files

I would have never guessed PDF Expert came with an unzipping feature if it wasn't for the contextual menu on a system app such as Mail. For my surprise, my attempt to open a zipped email attachment went much easier than usual thanks to this simple touch.


You will first need to tap on the attachment icons that appear at the bottom of the email body — this is normally used to download heavy attachments that you might not necessarily need to download now. For our test, just tap on file icon and wait until you get some type of button with blue text like in the image below.

Without any third-party app install to handle this task you would get the infamous "Mail cannot open this attachment". With PDF Expert though, the contextual menu will allow you to either open with the app of forward it elsewhere via email.

The app does not only unzip the file but it also understand folder structures. This allows you to navigate though the usual nested folders containing all type of supported documents (such as images), flicking through them as if they where part of a photo gallery on the Camera Roll. In the main PDF Expert window you can either organise elements on a list view or on a grid, which will render a miniature of the image or the PDF document in question. A handy tip: it's possible to drag and drop items into folders to keep things tidy and organised.


This secondary feature in PDF Expert has become tremendously convenient to handle all type of attachments that arrive in my email inbox, be it a my payslip or a folder of screenshots of an app for review. PDF Expert is, of course, much more than that. It's advertised as a proper tool to handle documents, opening and reading without the pain of free options like iBooks. It's also cloud aware, being able to sync very quickly with Dropbox and Google Drive.

Additionally, PDF Expert includes pro functionality from filling in forms, annotating, saving changes as a flattened PDF document or protecting the app content with a password. The iPad version will probably give you more real state to work with long documents more comfortably, but this demonstrates the power of post-PC devices as standalone machines, at least for getting some work done on the go.