Previewing Our New Cloud Services: Sencha.io

Earlier today at the Sourc{ conference in Split, Croatia we previewed two new cloud services from Sencha. To distinguish them from our SDK’s and tools we’re calling them “Sencha.io” services. The goal of Sencha.io services is to provide common application functionality as cloud services so that application developers (particularly mobile application developers) don’t have to reinvent the wheel every time they want to make an app. Our first two cloud services solve two common problems for app developers – resizing images for different mobile screen size/resolution combos, and making offline and collaborative data synchronization easy.

h3. Sencha.io Src

The first service we introduced was Sencha.io Src, which helps mobile apps resize images for the ever increasing number of mobile screen sizes. We’ve previously done a lot of work in Sencha Touch to make your UI resolution independent, io Src expands this to include your image assets. And it’s easy to use, simply add http://src.sencha.io in front of your IMG tags and Src will automatically scale the image appropriately from the origin to the right size for that mobile browser. The benefits of using SRC is that the browser doesn’t have to resize a one-size-fits-all image inplace (which helps performance), or download more image than it needs (which improves latency).

Not only does Src perform automatic manipulation based on the device’s screen size, but it also has a complete API to let you customize how to scale your image, ranging from simple scales and skews to using it within data URIs. To ensure the best performance in a mobile scenario, original and resized images are cached by Src for 24 hours and the correct caching headers are sent to the mobile browser. If you’re familiar with tinySrc, Sencha.io Src is built on the same codebase and technology as tinySrc, which already serves millions of requests a month helping hundreds of mobile sites deliver a better experience.

Best of all, we’re excited to announce that it’s available today and at no cost for any reasonable usage. We’ll be bringing premium features to Src in the future, but rest assured that the basic service will be free forever.

If you’d like to check out Src in action, head over to Teagrams and see how the Teagrams app uses Sencha.io Src to dynamically resize images from Instagram. You can take a look at the source on Github as well. Teagrams is best viewed on a tablet. We’ll be be making the full documents available later this week.

h3. Sencha.io Sync

We also previewed Sencha.io Sync, our multi-master synchronization service that allows Sencha Touch apps to take their data offline and sync their models. We decided to start work on Sync after hearing from developers (and from our own experiences!) how unreliable mobile networks can be. Since Sencha Touch and the entire Ext JS platform is moving to a MVC pattern we realized how well built the “M” in our architecture was suited to enable apps to go offline and sync as well as to collaborate on a shared data set.

Using Sync, apps can operate offline, ensuring that all writes made to the local storage are replicated to the cloud master; apps can use Sync to backup data so the cloud has a replica of everything that’s in the client, and to recover data if the mobile data set gets lost. Better still, since Sync is multi-master, if an app expects a user to be on multiple devices, the data set can be edited and synced seamlessly between devices; or, if the app is multi-user, the same data set can be edited by multiple users from their own mobile devices.

Essentially, Sencha.io Sync provides the app with a distributed object store. A complete replica of the entire object store is available to each client, and each replica can receive updates and exchange updates with its peers through Sencha.io Sync. Think of it as peer-to-peer Sync in the cloud. If you’re interested in seeing some demos, open two browsers (e.g. Safari and Chrome) and open a tab in each for either Contacts and Crosswords. In Contacts, you can edit the data of the address book, replicate it to Sync, then hit the circle arrow in the other browser and the changes propagate. In Crosswords, each change is replicated and automatically synched between each client allowing multi-player gameplay.

Sencha.io Sync is an state-based object replication (SOR) mechanism. There are many other flavors of replication and synchronization, but we think SOR is the most widely useful and applicable synchronization scheme that can work with a wide variety of apps. Unlike log or diff based replication, SOR can lose intermediate updates without corruption – which is handy when you’re on a semi-connected network. It’s also a more general purpose synchronization scheme than niche-ier approaches like Operational Transformation, which is most useful when doing synchronization within a list-object – for example Google Wave-style live collaborative editing.

We’re in the early stages of Sync and it’ll evolve as we work to get customer feedback. As of today Sencha.io Sync is in limited preview and we’re opening invitations for people who are interested. For more information and to sign up, please visit the Sencha.io page.

h3. Road Map

We’re excited in the coming months to share more about this new set of cloud services from Sencha. Src is available today and over the next few months we hope to expand the feature set and build out premium features that continue the mission of helping developers manage the complexity of mobile devices and enhance the speed of mobile delivery. Sync is in limited preview and we hope to role out a larger beta in the later summer.

Lastly, since this is a developer preview, please understand that everything might change. We want to make sure we’re sharing where we’re going with our community early and often so we can incorporate feedback properly. We look forward to seeing how you use the Sencha.io cloud services! Request an invitation today!