While the top 10 tech start-ups may vary based on personal opinions and the specific tech industry, here are ten promising tech start-ups to watch in 2022:

1. Stripe: A global payment platform that enables businesses to accept online payments. It has experienced significant growth and is valued at over $95 billion.

2. Rivian: An electric vehicle manufacturer focused on producing electric trucks and SUVs. They have gained attention for their innovative designs and have received significant investments from companies like Amazon and Ford.

3. Algolia: A search and discovery platform that enhances user experiences by optimizing search functionality. It offers tools for developers and is used by companies like Twitch and Slack.

4. Snyk: A cybersecurity start-up that specializes in identifying and fixing vulnerabilities in open-source software. Their platform helps developers proactively address security risks.

5. Gong: A conversational analytics and salesforce training platform that helps organizations improve sales and customer interactions. Their AI-powered platform analyzes sales calls and meetings to provide insights and recommendations.

6. Cameo: A platform that allows users to request personalized video messages from celebrities and influencers. It has gained popularity and attracted celebrities from various fields.

7. Ginkgo Bioworks: A biotech start-up leveraging synthetic biology to create genetically engineered organisms for various industries, including agriculture and pharmaceuticals. They have raised substantial funding and have partnerships with major companies.

8. Samsara: A fleet management and industrial IoT start-up that offers connected sensors and software solutions for monitoring vehicle fleets, industrial operations, and more. It provides real-time insights, analytics, and operational improvements.

9. HashiCorp: A cloud infrastructure automation company that provides open-source tools like Terraform and Vault for managing infrastructure and security. They have a strong developer community and are known for their DevOps-focused solutions.

10. Figma: A collaborative design platform that allows teams to create, prototype, and collaborate on designs in real-time. It has gained popularity for its intuitive interface and effective team collaboration features.

These start-ups have shown tremendous potential and innovation in their respective fields, making them worth watching in the coming year.