Travis CI is primarily used for testing open source projects hosted on GitHub, while Bitrise is a universal continuous integration and delivery service that supports various development platforms and languages, including mobile development projects. A key difference between the two services is that Travis only works with GitHub, whereas Bitrise supports multiple git hosting providers and allows users to use their own private repositories. Bitrise utilizes steps as atomic building blocks, rather than a job lifecycle like Travis, and offers a more flexible workflow setup approach through its step-based workflow editor. Additionally, setting up Bitrise requires less effort compared to Travis, but it also means that users need to set up webhooks for GitHub pull requests to replicate the automatic status check feature of Travis. Overall, Bitrise is considered a good alternative to Travis CI and offers a powerful and flexible platform for continuous integration and delivery.