What is HelloWords Streak Saver and how can I get it?

The HelloWords Streak Saver helps you make up for missed daily vocabulary check-ins. By using a Streak Saver, you can keep your streak of consecutive learning days going and avoid losing it if you miss a day. You’ll get one Streak Saver after your first streak of 7 consecutive check-ins. Just a heads up: each user can only receive one Streak Saver.