Encrypt data using AES and 256-bit keys

AES stands for Advanced Encryption Standard and is an industry-standard algorithm for encrypting data symmetrically which even the US government has approved for SECRET documents. If you don’t know what symmetrical encryption is, it means that you use the same key or password to encrypt the data as you do to unencrypt it. So you need to keep the key extremely secret however it’s still incredibly useful. I’ll show you how to use openssl to encrypt some data and decrypt it using the Common Crypto libraries on iOS.
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Quick way of cleaning HTML for iOS apps

For some reason HTML is always dirty, it’s usually full of Analytics tags, JavaScript or contains nested HTML tags. This is usually fine for displaying in browsers but at some point an iOS app will need to display HTML content and usually when it does, you need it to display clean HTML or only a small subset of HTML tags… all it takes is an unexpected tag and the whole document layout could be ruined. So here is a way of quickly and easily stripping HTML content down.
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How to build a Ghostbuster Proton Pack

Ghostbuster Proton Pack at night

I decided to go as a Ghostbuster for a fancy dress party recently. Of course all Ghostbusters need fully working proton packs complete with animated LED displays and electroluminescent glowing wires, so here are the details on how I built mine. It took about 3 or 4 evenings to build and involved Arduinos, lots of hot glue and over 92 LEDs! It is just a shame I missed out on the best fancy dress award that night because it looked ‘too realistic’!

Ghostbusters-pack-in-dark

The Ghostbusters proton pack lit up in the dark

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Beautifully-formatted Times and Numbers

Example of rendered proportional numbers and monospaced numbers

Example of rendered proportional numbers and monospaced numbers

Not all font instances are created equally! In iOS text is mostly displayed using proportional fonts, meaning each character width is trimmed and varies depending on each character. This makes the text easier to read and feel more natural and you’ll notice this on characters such as ‘i’ which will often be the thinnest character compared to say an ‘m’ character. However for numbers displayed in a tabular format such as times, figures and currencies you’ll want monospaced characters so you can tidy up the layout and visually scan the data quickly. So how do you do this?
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Eve of Apple’s World Wide Developer Conference 2015

Apple WWDC 2015

WWDC 2015 has come round again and I’m lucky enough to be in San Francisco attending again! So what’s the tradition? Well I’ve just scoffed down a huge pile of pancakes down at Mel’s Dinner and just picked up my badge and legendary WWDC ’15’ jacket. You know the developers are in town as these jackets decorate the streets of San Francisco just like the huge colourful Apple banners that appear down 4th street.

There’s such a lively vibe going on as 5000 developer gather in one spot to learn the latest stuff happening at WWDC. In less than 24 hours we’ll all start queuing at 3am in the morning to get into the main Auditorium for Apple’s big keynote at 10am. Yes that’s a good 7 hours but the people you meet in the queue during this time can easily become life-long friends – anyone who’s met me at 2am in the morning, jet-lagged, freezing cold on a chilly San Francisco morning and still doesn’t want to throttle me by the end of it is deserves to be my friend!

The epicenter of change

The epicenter of change

This is easily the highlight of the developer year, iOS 9 is hugely expected as well as the next version of OS X with the associated XCode tools. For iOS 9 I’m hoping for big improvements to Siri and Apple Maps. Apple Watch should feature heavily in the sessions too but most of this is all under-wraps until the keynote tomorrow so this is all just speculation. In the mean-time, I’m hoping to head down to the mothership – Apple 1 Infinite loop before a few beers tonight with my fellow attendees at the ThirstyBear Brewery Co. If you’re in town see you there. Here’s hoping tomorrow’s announcement will be just as exciting as the build-up!