A few weeks ago, I was on a flight and decided to use the downtime to catch up on email. I couldn't turn on my phone's data connection, but since I have my phone configured to download messages as they arrive, I figured that I could read and respond to my messages even without connectivity. My responses would be sent the next time I had a data connection.
Of course Murphy's Law came into play and one of the messages included an attachment I couldn't open. Since I had no data connection, I had no way of downloading an app to open the attachment until I got where I was going — and that got me thinking about a few apps that should be installed on mobile devices so that you can open the most common types of email attachments.
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