What's the best way to design a GATT Profile?

When designing your GATT profile, every choice—how many services and characteristics to use, and which operations (read, write, notify, indicate) to support—can impact your device’s performance, user experience, and battery life.

Here are some practical tips:

Services and Characteristics: How Many Do You Need?

• Keep it Simple: Use as few services (3-10) and characteristics (1-5 per service) as needed to support your use cases. Avoid overloading your profile with unnecessary data.
• Group Related Data: Combine logically related characteristics into the same service. For example, a Battery Service might include Battery Level (Read) and Battery Status (Notify).
• Plan for Growth: Reserve space for future features to avoid breaking changes in the profile.

GATT Operations: Choose Wisely

• Read: Great for static or occasional data, like firmware version. Use sparingly to avoid unnecessary battery drain.
• Write: Use Write Without Response for faster updates, and Write With Response for critical commands where confirmation matters.
• Notify: Ideal for real-time updates like heart rate or temperature. Balance update frequency to optimize power.
• Indicate: Use when data reliability is critical, such as for medical alerts. Keep these low-frequency to save battery.

A note about UART Designs?

A UART-style design—where you simulate a serial interface over BLE—can work well for simple, low-bandwidth data streams or for backward compatibility with legacy systems.

However, it often sacrifices clarity, flexibility, and maintainability, especially when data parsing becomes complex.

Finally -

Remember this is an iterative process. The first pass doesn't need to be perfect. You will be making more changes as you test and get more feedback from the mobile team.