The best alternatives to FrontSketch are Zight , Josh Parnham, and ScreenTray. If these 3 options don't work for you, we've listed a few more alternatives below.
What do you think of FrontSketch?
AssemblyAI— Speech-to-Text API with superhuman accuracy
A macOS app for capturing, annotating and sharing screenshots. Quickly add comments, highlight what matters or blur any sensitive content. Upload screenshots to Google Drive or Dropbox. Copy screenshots to the clipboard and paste them directly into Slack, Gmail, Jira, Trello and lots of other apps.
Browser based annotation tool. Free and easy to markup images. Upload any images or take screenshot of your screen. Without any accounts. Just annotate!