Download a free trial of sketch will only allow you to use it freely for a month. When the trial is expired, it will keep asking you for license keys; otherwise, you will not be able to use it at all.
Today, I’ll show a hack to keep using sketch without a license key.
For Sketch Version above 49:
1. Change your system time to a date that is before the date you downloaded the trial.
2. Open Sketch. Voila! You can use Sketch without any restrictions or warnings!!
3. Now once you’ve opened Sketch, while enjoying your Sketch, you can set your time back.
For Sketch Version below 48:
First, you open an image file (a png or jpeg or any other kinds) using Sketch.
The image will be opened, and you will be greeted with the alert to enter a license key.
It will ask you to save your work before quitting.
And now, you can create a new file via File >> New. In this new file, you can use Sketch’s full functionalities without a license.