PowerApps Functionality Modification

I'm seeking an experienced PowerApps developer to help modify the functionality of an existing app.

Key Task:
- Address a ComboBox issue related to filtering and adding a text field.

Ideal Skills and Experience:
- Proficiency in PowerApps, especially in modifying app functionalities
- Strong problem-solving skills
- Experience with ComboBox configurations and data handling
- Familiarity with app performance optimization

Please provide examples of similar work done.