Previews are unofficial releases of blueBill Mobile available for people who's eager to try new features and cooperate with the quality assurance of the project. In fact, these previews aren't tested for daily use - for this reason, they are not distributed by means of the Android Market or other official markets, but they need to be manually downloaded. For an open source project like blueBill Mobile, cooperation in testing new releases is a critical thing to make us able to release new official versions guaranteeing the broader compatibility to various phone and tablet models.
Previews can be installed side-by-side to the official version of blueBill Mobile. You'll see two icons in the application launcher menu and you can pick which one you want to run. This means that trying a preview won't affect your daily usage of blueBill Mobile. Previews are shown with the label ""blueBill Mobile (Development)" and (since 1.0-ALPHA-3) they have a slightly different icon (with some gears near the duck head).
There are three types of previews:
You need to enable the phone (in Settings / Applications) to accept "Unknown sources". Then, just enter the download URL (see below) into your phone's browser; the download should start. When it has been completed, open the notification area, where you should see a message such as "Download completed". Now, just click on it. The phone should ask if you want to install the app. Don't worry whether it says "The application is going to replace an existing application": it won't affect the official blueBill installation. In any case, it' always better to export your observations data before proceeding with the operation.
If you usually keep the option about "Unknown sources" disabled (you should), remember to reset it after you have downloaded and installed the new blueBill.
At this point of the release plan we're focusing on compatibility with all the phones. It's enough to know that the application starts on your phone (Android 1.5 or later, including Android 3.x tablets). The application, when started, sends a very short notification to us, including the brand, model and operating system version of the phone (no personal information or observation data is ever transmitted). In this way we can automatically collect some data about compatibility. Only if you experience a critical problem at startup (such as a crash or a notification about being unable to run because of low memory) we kindly ask that you notify us about the problem.
Usually, you should just try the latest preview. But if you can't run it, you might try an old one. Knowing that some previews don't work for you and others do it's a valuable information for us.