Build a project schedule without a training course, then send it as a PDF that every person on the team can read. Windows desktop. Your schedules are files on your computer, not rows in someone's cloud.
If you need multi-user cloud, use Smartsheet. If you need enterprise resource management, use Microsoft Project. EasyGantt is for the person who plans in Excel today, or fights a bigger tool than the job needs, and wants something simple that they own.
EasyGantt is new software from an independent developer, so Windows SmartScreen hasn't built reputation for it yet. Click "More info" → "Run anyway". The download page includes file hashes so you can verify what you got. Code signing is planned as the user base grows.
Nothing. Your schedules are human-readable JSON files on your disk, and the app never phones home or checks a license server — it will keep working forever. No lock-in is a design goal.
A father and son. The idea came from a working project manager who found the off-the-shelf tools too complex, and whose exported schedules the rest of the team could not open. The code was written by a software engineer with more than 40 years of experience building software systems, including factory automation work and a few years in a machine shop, who had run into the same problems himself. You'll get support email answers from the person who wrote the code.
There's a 30-day no-questions refund — buy it, build your current project schedule in it, and if it doesn't earn its keep, reply to your receipt email and you'll get your money back.