BlackBerry Messenger, or BBM, for Android and iOS (iPhone) has finally gotten an official release date, and according to BlackBerry (NASDAQ:BBRY), the cross-platform messaging app will make its way to iPhone and Android devices this weekend.

Buried at the bottom of the announcement was the sour news that many of the BBM features found in official BlackBerry devices will be missing. That means Android and iPhone BBM users will not be able to make video calls over BBM, which can be made over WiFi or data connections on the BB10 version of the app.

Voice calls through BBM are available over WiFi on BlackBerry devices, but that feature will also be missing from Android and iPhone iterations of the app. Emoticons, however, will be available on BBM across BB10, Android and iOS devices on the launch date.

It is finally official: BBM is coming on Saturday morning for Android users running on version 4.0 of the operating system, and iPhone users running iOS 6 and iOS 7 will be able to download the app one minute after midnight. BBM will become available as a free download for Android at 7 a.m. EDT on Sept. 21, and will then become available at 12:01 a.m. EDT on Sept. 22 for iPhone users. 

Although BlackBerry said that the missing features of BBM for Android and iPhone “are planned for availability ... in a future version,” reports also surfaced today that said the company would soon be laying off up to 40 percent of its work force. And BlackBerry's plans could potentially change if BBM software engineers are a part of that 40 percent, and since the future of the company is uncertain, it is impossible to determine what kind of app support users can expect from BBM for iPhone and Android.

BlackBerry has not disclosed whether the screen share feature will be included in the Android and iOS versions of BBM. Screen share allows users to send a full image of their screen over the app, and the company suggests that it can be used for technical support, working on group projects, among other things.

Reports earlier this summer said BlackBerry was considering a desktop version of BBM, although the company refused to comment on the rumor. BBM can be used to send pictures, audio recordings, as well as their map location and files under six megabytes.

BlackBerry raised hopes that BBM for Android and iPhone might be released this Wednesday after inviting the press to a Malaysian event that day. However, the event turned out to be the unveiling of the previously leaked follow-up to the BlackBerry Z10 -- a phablet called the BlackBerry Z30. 

An official Samsung Mobile Nigeria Twitter account responded to a user’s tweet that had many wondering if the Korean manufacturer had snagged a three-month exclusive on BBM for Android for its Galaxy smartphones. BlackBerry denied the tweet, and confirmed that all Android devices running Ice Cream Sandwich and Jelly Bean versions  or newer will be able to download BBM.

BBM in an instant messaging service that has been a mainstay of BlackBerry devices since the feature phones’ heyday in the early 2000s. BBM allows users to set a “status,” which contacts can see, similar to AOL Instant Messenger, which was released in 1997 and remained a popular desktop application for several years.

A BBM sent from one device usually travels through data frequencies faster than a standard text message, or SMS, which travels through older and slower networks. BBMs have a text limit of up to 2,000 characters, as opposed to the 200-character limitation on text messages. BBM 7.0.1 brought emoticons to the messaging app, and earlier versions included near-field communication, or NFC, support and QR codes for sharing the BBM pin, which is what users use to connect instead of a phone number.

Android users looking for BBM should be careful searching for the app in the Google Play Store, as numerous fake versions have appeared that install malware, including adware and viruses, on devices.

Amidst the reports of deep staff cuts, news surfaced that BlackBerry is also attempting to sell itself by November as handset sales continue to plummet, and it is considering spinning off BBM into its own separate division.

International interest in a cross-platform version of BBM is high as mobile-device users in expanding markets look for ways to avoid short message service, or SMS, charges from wireless providers. BBM for Android, iOS and BB10 sends and receives messages via mobile data plans, and since the messages contain a very small amount of data, users are able to communicate more for less than it would cost to send a standard text.

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