How to setup Try’n’Buy product at RIM/BlackBerry App World

Interlecta Translator at App WorldThis is based on my personal experience while resolving issues with the products of our company Interlecta, and it is not a general solution.

Start with a new product

It is always better to start with a new product. Don’t use previously created product that was free or paid – the time you could save by doing that will cause more troubles afterward.

This is mostly because the existing user that have already downloaded previous versions will have problem upgrading to the new release, either “try” or “buy” one.

Incremental versions

Cannot get the correct version. One of the first problems that usually occurs is that people cannot see the correct version depending on whether they have purchased the product or not. The issue present almost in all cases when someone downloaded the trial and then purchases the full version – the result is that they cannot download the full version because it is not available on the screen.

Interlecta Translator at App World

Cannot upgrade. Another case would be when there is an upgrade of the release. They see the message, a notification by App World, that there’s a new version but there’s no button to download it.

Always increment versions. What we have learned while trying to resolve those issues was that the versions should be always incremental, i.e. the “buy” versions should be greater that the “try” version. Example: our Interlecta Translator trial was 1.3.19 while the full version was 1.3.21. That makes sense from database design point of view, but it’s not convenient at all, and such behavior is not documented, you have to learn it from experiments.

Problems with upgrading to full version

This is a common problem.

Canno upgrade to new release. If you have new release of your Try’n’Buy product people will receive a notification but when they go to the product screen at App World they will not be able to do the upgrade simply because there is no button for doing that. In our particular case there’s only a button to install the trial version.

Interlecta Translator at App WorldAn experiment worth trying. What we’ve found out is not a solution, but is more like a work around, it’s annoyingly slow process, but it’s ate least something that may help your customers. In short, you have to: Remove your application from App World; Remove the App World itself; Reinstall the App World; Login to App World through PayPal; Reinstall your application. It also involves rebooting your BlackBerry 4 times. That’s not convenient at all, but was the only was for me to get the latest full version.


More details were posted on our company blog at

There’s also discussion at supportforums forums:

Please share your experience following the steps above, either here or on our company blog.

Haitian Creole available for Interlecta Translator (RIM/BlackBerry App World)

Haitian Creole for Interlecta Translator

Haitian Creole is now available for testing on Interlecta Translator for BlackBerry, downloadable at RIM’s App World application store.

Just couple of hours ago we have finished the first testing version of the new functionality of our BlackBerry application – Haitian Creole.

I have to admit that recently I’ve been talking with quite few people about our initiative to provide Haitian Creole, and especially Marian Douglas-Ungaro. We spent last several days looking for the best technologies to combine to bring that new feature to life, and finally today late in the afternoon we’ve managed to get the first translation on my BlackBerry from Engliush toHaitian Creole.

I don’t know how many people will download this and use it and how many of them will be doing anything in Haiti, but I’m glad that are able to provide that service. And not only that, we are the first company to offer that kind of software for BlackBerry.

The product, Interlecta Translator with Haitian Creole, is available for download at App World. There’s 7 days free to try download, but for some regions and countries it is available for free – just open App World on your BlackBerry and do a search for Interlecta to find out.


Implementation of FNV hash in PHP

FNV is a simple algorithm and produces good results.

I needed this functionality as part of another project that required automated generation of relatively large number of unique usernames based on information provided by the user.

Some challenges:  Apparently PHP does not work well with numbers, especially large ones. I spent few hours trying to find out why my implementation was not producing correct results, … realized in the end that arithmetic with big numbers is something you should not do with PHP. To resolve these issues I had to use bitwise shift and add operations instead of multiply.

I put the code here:

… and a simple wiki page here:

More information about the Fowler-Noll-Vo hash function could be found here:

Lecture about Mozilla at the University of Veliko Turnovo

Thanks to the kind cooperation of Interlecta, a lecture about Mozilla in Veliko Turnovo is to become a fact.

Bogomil Shopov will talk about the history of developing the open source browser Firefox, since the first Mosaic through Netscape, Phoenix till its present version and the browser’s upcoming fifth birthday.

The second and more interesting discussion will be about open web as Mozilla’s vision on this subject is fundamental about the Internet freedom and sharing, the adequate usage of the web, and the right to own one’s personal information and contents in the world wide web.

Several of Mozilla’s products will be presented in the third part of the lecture and it will be outlined how everyone can contribute to their development.

According to the information published on Novinite website (a Bulgarian news release website) Mozilla in Bulgaria is more popular than in the rest of the world as a whole. In Bulgaria Firefox is used by 39.1% of users and by 23,75% in global plan.

In October last year Interlecta released the Firefox translation add-on MozTrans which gained popularity very quickly and is now used by thousands of users.

The lecture will be on Thursday, October 15th, in Corpus 3 of “ Cyril and Methodius” University of Veliko Turnovo, starting at 4:30 p.m.

Interlecta featured on App World


Our product for BlackBerry was promoted as a featured application on RIM/BlackBerry App World, check this out – App World – Webstore. Currently we are getting about 300 downloads every hour – couple tousands of downloads just for today. I’m excited about it.20091002-2118_InterlectaAppWorld_2001_crop364x242

UPDATE: We were getting over 10000download every day, it seamed that people really liked it.

Calendar Generator – something very simple

This is something very simple.

It happens that I often need to print various calendars, like weekly or monthly, to keep track of my task and later to use for reports.

I wrote this very simple PHP script that will output a week calendar on the screen that printed will spread on the entire page.

The information is published at GoogleCode:

The code is available though Hg (Mercurial) at or for direct browsing at

Opened GoogleCode account for prototypes

I decided to share my prototypes at GoogleCode. The page is located at

I was looking for a place to store some of the code that I write from time to time. I needed something reliable that is free and that will last for longer. There are may hosting services offering storage for open source projects, like SourceForge, and they all have their pro’s and cons’. The features I was looking for were: source code repository; download facility; content management. I found GoogleCode quite convenient and convincing, so I decided to create a page there.

Another reason to make that choice was that there is offered Mercurial version control, I thought that it is time to start using on of the distributed version control system.

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