8 Best Open Source Software in 2026

Cal has changed the meaning and expectations when it comes to the standalone scheduler app category as it's the most flexible, and modern scheduling software on the market.

While Calendly was the leader in the meeting scheduling space for the past decade, over the past few years Cal has given them a run for their money, and in our opinion, has overtaken them.

Cal is by far the best overall meeting scheduler for individuals, SMBs, startups, sales & customer support teams, and even enterprises because they are incredibly flexible. Schedule meetings & appointments (checking multiple team members calendars), set up recurring appointments, take payments with scheduling, and create custom workflows.

Where meeting schedulers have become more of a feature of a product, like that of Motion, amongst others in the best calendar apps space, Cal has doubled down on that fact by not only making their tool open source core, but by also giving a robust API, allowing you to use their scheduling infrastructure for your own product. This makes it ideal for our more technical friends, enterprises, educational institutions, or even doctors offices.

That said, if you only need a basic meeting scheduler for 1:1 meetings, Cal is likely more than you need. Many of the best daily planner apps, project management tools, and even the best email clients now have a scheduler built in, so it's worth trying what you already pay for before adding another tool.

• Free: Best for individuals who need simple scheduling with no usage limits.
• Teams: $12/mo per user (billed yearly). Best for small teams and startups that need collaborative scheduling features.
• Organizations: $28/mo per user (billed yearly). Best for larger teams that need more control, security, and advanced routing.
• Enterprise: Custom pricing. Includes dedicated support, SLAs, advanced integrations, and enterprise-grade infrastructure.

Inbox Zero (not to be confused with what Superhuman Mail refers to getting through all your emails) is a layer atop your Gmail that helps you to easily unsubscribe from newsletters and automate label/forwarding flows all via AI.

The area that we use and love with Inbox Zero is where it helps us tame our email inbox, sort of like Mailman, but it focuses more on actually leveraging AI to automatically take action on your email (or unsubscribe if you're getting many newsletters but not reading any of them.

• Basic: $6/month on annual tier + $1.50/month for each additional email account
• Business: $12/month on annual tier + $3/month for each additional email account

Let us save you the time and research: whether you're a creator, marketer, or a company looking for a link infrastructure there is no better solution than Dub, trust us, we've tried them all.

Dub is the most modern link shortening/analytics platform. If you've tried to use Bitly's analytic dashboards (or Short's), but they are horrendously kludgy 🙈 So much so, that they cause dread to even go into the back-end.

Dub on the other hand, provides a minimal UI, providing you with the analytics in crystal clear dashboard. With Dub you can easily spin up short links, QR codes, add tags for organization, and even enable things like password protection, expiring links, or geo-targeting.

All of this, AND they have the most generous free tier of all the tools out there to try it out. If you're looking for a new link shortener, Dub is hands down the best on the market.