I'm currently intending to add a scheduler from my rails app. Is there
any recommendable plugin or gem to achieve this? I don't prefer to use
cron as I want it to be bundled inside the application.
Many thanks for your recommendations.
Write yourself some rake tasks to do the scheduled jobs you need.
Then write yourself some rake tasks, like "daily" which run all the daily tasks you need to happen.
Then use cron to run your "daily" schedule.
Now, when you need to update the daily jobs, you just modify your rake tasks and redeploy your app. No need for further interaction with cron.