This weekend has been surprising for me. Firstly, it has seen the start of some contract iPhone application work which I managed to pick up. Secondly, I have been contacted about joining with a couple of people to start looking into the market potential for mobile applications. And thirdly, I have been contacted asking if I’d like to apply for a job developing mobile applications.

All of these points have made me realise just how big the market is for mobile applications, and just how much of a growth area it is likely to be over the coming months / years. It’s very exciting and I am looking forward to being part of such an exciting industry. I’ll try to keep blogging about things I find out and hopefully others can learn from my thoughts or just enjoy reading what I am finding out.

When I released Subnet Calc Pro, I worked out how many hours work I did on it and therefore how much money I would like to get back from it. Then I decided a price based upon how many sales I thought that I would get. I managed to achieve my money goal after just under 3 months of selling which I thought was extremely quick as I had imagined it would take more like a year to do that!

Since the release of the first beta of the 3.0 SDK I’ve been checking if apps built for 2.x can run on it. Clearly this is something which Apple really should do, but a hint in the latest (beta4) release notes says this:

FIXED: Previously, the compiler incorrectly allowed synthesis of ivars belonging to a superclass. This caused crashes or other undefined behavior when the size of the superclass changed (such as running an application compiled against an older OS on iPhone OS 3.0.) The fixed compiler now generates an error when it encounters this condition. If you have shipped an application to customers, Apple recommends compiling against the 3.0 SDK and updating your existing application if the problem exists.

Now, does that mean that you’re going to have to release an update for apps which exhibit this problem for people on 3.0 to be able to use the app? Surely that cuts out people who upgrade, and if you update your app then it cuts out people who don’t upgrade? Lose-lose situation?

I started using the lovely json-framework for the iPhone but then suddenly found that if I compiled for anything greater than 2.1 for a device, that it would pop up with:

Codesign error: “object file format invalid or unsuitable”

It took me a long time to figure out what was going on, but thanks to a blog post, the fix is this:

On the project settings, on the build tab, search for “Code Signing Resource Rules Path” and set “$(SDKROOT)/ResourceRules.plist” as its value.

I’m not sure how it works as it looks like that is the path it already has, but hey, it seems to work!

Today I reached my target for what I had in mind when I created Subnet Calc Pro! I won’t disclose how much this is, but I can say that it’s more than I initially expected, but not enough for a monthly wage! It took me just under 3 months of sales to reach the target which in my opinion is pretty good.

My experience at getting from a non-iPhone developer to successful application selling on iTunes has been an interesting ride which I have enjoyed very much. It’s exciting to be part of what seems to be a great technological revolution.

My current efforts have been focussed on my new app, BeerMap which I am hoping shall be released soon!

Over the weekend my new application, WhoseRound, was released. This is a fun application which allows you to draw straws for deciding quite literally anything. Basically, whoever ends up with the red fingerprint is the person who has been chosen!

Ok, there’ll be plenty of these kind of post floating around, but I wanted to get my thoughts written down anyway.

Before the iPhone event today, my thoughts on iPhone OS 3.0 were that it would be a worthwhile upgrade and I was excited to see what new features Apple had in store (you can ask anyone at my work and they’ll say how excited I was!). But it turned out that Apple went far above and beyond what I had expected…

Subnet Calc Pro has now been out for just over a month and I can safely say that it’s had a lot more uptake than I thought it would! It’s not been massive in sales, but the best thing is that it has been steady. It’s not going to mean I can quit my day job, but it has meant I feel rewarded for my hard work of learning a whole new programming language, fighting through Apple’s tax forms and releasing an application.

I have been playing with SQLite recently and toying with the idea of creating some kind of framework upon which I could build persistent data objects, much like the Zend way of doing things in Zend Framework for PHP. That was, until I came across SQLite Persistent Objects…

A few weeks ago, Softpedia reviewed Subnet Calc and classed it in their freeware picks section. So when I released Subnet Calc Pro I thought I’d let them know. They have kindly responded by reviewing Subnet Calc Pro.

Hopefully this will be the start of something more with respect to iPhone apps. I’ve got plans for others, which I will be starting work on one of them soon. It’s quite an interesting app which uses the GPS function of an iPhone which should be fun to try and play with!