Jobber is really just cron + support for error-recovery strategies like exponential backoff + support for getting the job execution history. It is very simple to deploy: it consists of just two (native) binaries, and has no dependencies (well, other than Bash).
Chronos also supports these additional features (although I don't know about exponential backoff), but Chronos is much more ambitious than Jobber. Probably the biggest differences are that Chronos supports farming jobs out to other nodes and that it supports dependencies between jobs. And of course Chronos has a nice GUI. On the other hand, I imagine it's a bigger deal to deploy, although I haven't done so myself.
So, if you have a bunch of related jobs that need to run on multiple nodes, Chronos would probably be best. Otherwise, try Jobber!