Saints Row does have an online co-op feature that allows you to partner up with your friends and tackle the campaign missions together. However, that's how far you'll get from getting full-pledged online gameplay compared to the vast open-ended options from Grand Theft Auto Online. Based on an interview with the developers of the Saints Row Reboot, you should be expecting to see the same co-op mode within the reboot. This co-op mode is a step up from Grand Theft Auto's solo player campaign, but we may see that change once Rockstar announces Grand Theft Auto VI.