Category Archives: Corona SDK

Develop and publish mobile apps for free

Corona Labs announced a completely free version of Corona SDK for developing and publishing mobile apps and games. This is great news for anyone who wants to create apps without paying a single cent. Students, indie developers and hobbyists would benefit most from this announcement.

What’s the catch? Well, there really isn’t one, except the new Starter version does everything the Pro version did, minus these three features: In-app purchases, analytics, and access to daily builds. Corona Labs doesn’t even require their splash screen to be displayed like some other “free” SDKs. A developer can use the Starter version to make apps and earn money by either charging up-front, using ads, or other means.

You’re probably thinking why would Corona Labs make this move. The reason is simple: Attract more developers to their platform (SDK and Corona Cloud). If developers feel the need for the three features and upcoming “pro” features, they would upgrade to the Pro version. Some pro features Corona Labs mentioned they’re working on include: new graphic features using OpenGL 2.0, plugins, device access through native code (maybe, but not full-blown like the Enterprise edition).

For existing developers with Indie subscription, they’re now automatically upgraded to the Pro version. For Pro subscribers, they get two extra months of subscription. For Enterprise subscribers, there’s no change.

There is, however, a price increase for the Pro version starting May 1st, 2013 from $349 to $599 per year. For pro subscribers, as long as their subscriptions are not expired by April 30th, they can upgrade twice at the old price of $349. For anyone who wants to take advantage of the lower price (for the next two years), subscribe by April 30th! More info at their pricing page and the conversation with their COO.

As a side note, Corona Cloud is an exciting server solution for any developer (not just Corona developers) who needs features such as User accounts & authentication, Leaderboards & Achievements, Multiplayer, Push Notifications, Social Connect, Cloud Sync, Chat, News, and Analytics. This simplifies greatly dealing with the server from a developer’s point-of-view.

For those who are interested, Walter Luh (CEO of Corona Labs), will be coming to FITC Toronto this month. His presentation is Building Native Apps: A Digital Canvas for Coders and Designers.

Off to making apps that people love…

Screen scaling for different devices

In multi-device development, one of the issues to deal with is displaying the same content in different screen resolutions. Corona SDK offers a simple solution by specifying the scaling mode in the config.lua file. The scaling modes include: none, letterbox, zoomEven, zoomStretch. Sometimes it’s easier to understand by seeing the visual difference than reading the docs.

Below are the 4 modes displayed in four different devices (starting top-left clockwise: Galaxy Tab, iPad, iPhone & iPhone 4). The background photo is loaded at the Galaxy Tab screen resolution (1024×600).

To view the original full-size images, click on the images to view at Flickr (then choose Actions -> View all sizes), or use the links at the bottom of this post.

 

None

Screen Scaling None

 

 

Letterbox

Screen Scaling Letterbox

 

ZoomEven

Screen Scaling ZoomEven

 

ZoomStretch

Screen Scaling ZoomStretch

 

The source files used to create the display can be downloaded here. The four full size images are here: None, Letterbox, ZoomEven, ZoomStretch.

Hope this is useful.

 

Another 3rd-party iPhone SDK: Corona

Corona: Another 3rd-party iPhone development SDK is now open to developers for pre-beta testing.

One thing that sets this SDK apart: The engineers are “former Adobe mobile software veterans” who worked on the mobile Flash ecosystem.

And no, the programming language is not ActionScript or JavaScript, but is Lua – a simple scripting language that should be easy for ActionScript developers to pickup. One thing uncertain to me is whether Corona is generating native Objective-C code from Lua code, or simply interprets the Lua code at runtime (I certainly hope it’s not the latter).

At the moment, there is no public distribution build. The only way to test a project is by using the Corona Simulator that comes with the SDK. Corona is still at its early stage, and the final product is targeting end of Q3 2009.

As Apple has been known to reject apps for unknown reasons, many PhoneGap developers have encountered the most-feared notice that their app is rejected. One possible reason is PhoneGap relies on the Safari JavaScript engine, and JavaScript code is interpreted at runtime, which is not allowed by the Apple SDK agreement.

For me, there are some important questions:

  1. Does Corona generate native Objective-C code or interprets Lua code at runtime?
  2. How much does the final distribution license cost?
  3. How stable is the final code?
  4. Is memory management handled efficiently?

Nevertheless, it is good to see more 3rd-party tools and SDKs for iPhone development.

Update: Today (June 24), this article talks about Corona. “When the developer has his Lua code the way he wants it, he submits it to the Ansca Web site, where it will be compiled into an iPhone application ready to submit to Apple’s App Store.”

Even though it seems to simplify the workflow, this may not be ideal because:

  1. the complete project and code is submitted to Ansca
  2. sounds like the developer does not get any Objective-C code for tweaking
  3. developer is locked into Ansca’s terms for future deployment

Hopefully Ansca would address these concerns in their FAQ or forum soon.