Here are the top 5 productivity apps:
1) To do list: A task management app that allows you to create and organize to-do lists, set reminders, and track your progress.

2) Evernote: A note-taking app that helps you keep track of ideas, organize information, and collaborate with others. https://www.evernote.com

3) Slack: A communication app that streamlines collaboration and communication within teams. Available on both Android and I store

4) Google Calendar: A calendar app that helps you manage your schedule and stay organized.

5) Focus@Will: A productivity app that provides background music specifically designed to increase focus and reduce distractions Enjoy Free Access Here 

These apps can help you to stay organized, manage your time effectively, and increase productivity. However, the best productivity app for you will depend on your specific needs and preferences.

Hope it helps

Let me know which productivity enhancement app/tool do you recommend?