Google has closed even more services as it continues its "spring clean" to focus more on core products.

In total eight services will be affected in Google’s latest product cull. Perhaps most significant of these is Google Sync for BlackBerry. Google will stop support for the app, which enabled users to download contacts and Google Calendar events to BlackBerry devices, and uploads contacts and Calendar events from your BlackBerry to a Google account, on June 1, 2012.

Google is encouraging users to switch to BlackBerry Internet Service (BIS) or the Google Apps Connector for BlackBerry Enterprise Server, both of which offer a better service and enable users to sync email messages, calendar and contacts through a single service, Google said.

Also on the hit list is the mobile web app for Google Talk, which will be closed in favour of native Google Talk apps for Android and other mobile platforms.

Picasa, Google’s image management platform, is also impacted, with the closure of WINE-based version of Picasa for Linux. Matthias Schwab, director, Cloud Services at Google said that, "As we continue to enhance Picasa, it has become difficult to maintain parity on the Linux version." Google will no longer be updating the product, although it will still be available to use.

Picasa Web Albums Uploader for Mac and Picasa Web Albums Plugin for iPhoto are also going – Google suggest using version 3.9 for Mac, which contains these features built-in.

Google Related, which the company describes as a "browsing assistant launched to help people find interesting and useful information while they browse the web," will also close as adoption has been poor.

Other products to go include: Flu Vaccine Finder, One Pass, a payment platform for online news publishers, and Patent Search homepage, which will be incorporated into the main Google.com homepage search.

"Focus is crucial if we are to improve our execution. We have so many opportunities in front of us that without hard choices we risk doing too much and not having the impact we strive for," Schwab added on the company’s blog.

"Making changes to products or services is hard, but we do need to maintain our focus if we are to do important things that matter in the world. As we continue our clean-up, we look forward to creating a simpler, more beautiful user experience across Google."

Google’s product cull over the last few years has seen the company close services which it does not see as mission-critical or that are not seeing the expected level of user interest.

For example the arrival of the Google+ social network meant that Wave and Buzz were closed, as was Jaiku. Google Labs, its testing site for new products, was also closed during a recent spring clean.