When comparing SourceForge vs Launchpad, the Slant community recommends SourceForge for most people. In the question“What are the best source code hosts for open source projects?” SourceForge is ranked 5th while Launchpad is ranked 8th. The most important reason people chose SourceForge is:
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Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Useful business software comparison system
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Pro SourceForge offers a lot of helpful features for open source projects
Every project hosted on SourceForge can have discussion boards, and issue tracker, a tab for screenshots and something most code hosts don't have: a Shell access. Developers can also websites for their projects for free on SourceForge, as well as a Wiki for documentation.
The downside to this is that there is a lot of clutter in the beginning, and it may take a long time for beginners to check what they need and what they don't and where everything is.
Pro Easy for downloading projects
SourceForge makes it easy for users to download software hosted on it. It detects the user's platform and provides them with an appropriate version. They also have an extensive mirror network all over the world, which helps speed up downloads.
For developers, they offer download stats which are grouped by platform and by region.
Pro Safe downloading
Malware Scanner ensures safe downloading.
Pro Good support
Support is quick & ticket creation and follow up system is good.
Pro Support for web based translation
Launchpad makes it easy to translate free open source projects into virtually any language in the world. Users are allowed to start working on translating any project they want just by having a Launchpad account and a web browser. Most of the time they don't have to even join a team to start working and the editor is web based, so there is no need for any special software.
Pro Integrated build/deployment system
If you use launchpad, it gives you a build system (on their platform) as well as easier deployment - user merely adds your PPA to their sources.list file. Deployment (on Ubuntu, at least - other debians as well) doesn't get simpler than this.
Pro Great bug tracking features
Launchpad is built to be used for open source projects, as such it needs a powerful bug trackers to allow developers who want to contribute to jump right in. Launchpad displays bug statistics (total number of bugs, number of bugs fixed etc...) as well. Bugs can be searched and displayed from every project hosted on Launchpad or for single projects.
Cons

Con Cluttered UI
Compared to other hosts, Sourceforge's UI feels messy and cluttered. Ads take up large portions of screen real estate, and feature creep has resulted in buttons and links everywhere that can sometimes make it difficult to find what you're looking for.
Con The web interface is complicated and hard to use
Other project hosts such as GitHub, BitBucket or GitLab have easy, simplistic UIs that help new and experienced developers alike to browse code right through the browser. LaunchPad on the other hand is very weak at this. Most of the projects have poor (if any) documentation and no way to determine a project's worth easily. The fastest way to do so with LaunchPad would be to download the project and look through the code manually, which is quite tiresome.
