200i offers inreach messaging, 200 does not. 

Other Features:

• Measures dogs’ speed and distance travelled
• Dog Trails: Choose from three views: Complete History, Partial History, or no Trail History
• Map Screen option: Show / Hide Dog’s Status, Distance, Names, and Off screen Dogs
• Zoom to MAP DOGS – automatically zoom in/out to include all dogs appear on the map screen — no matter how far they are from you
• Wireless sharing of Dog info to other ALPHA handheld units
• 16GB internal memory – install extra maps
• Expandable external memory by micro SD card
• Comes with Australian Topactive Map
• BirdsEye direct to device without annual subscription required
• Waterproof
• Rechargeable with user replaceable battery
• Trip Computer

The Garmin Alpha 200 GPS dog tracking handheld is the new addition to the touchscreen Alpha Range product. It is compatible with Garmin T5x / T5 mini collar for tracking as well as TT15x /TT15 mini collar for tracking and training. It has new larger 3.5 inch capacitive touchscreen which is a sunlight-readable touchscreen. The improved 6 button design is great for fast training cues and minor adjustments in the field.

General
Physical dimensions: (6.8 x 16.2 x 3.4)
Weight: 280g with standard antenna and battery
Water rating: IPX7
Battery type: rechargeable lithium-ion (included)
Touchscreen: Yes
Display type: Transflective, colour TFT touchscreen
Display size: 4.7 W x 7.7 H cm; 3.5 inch diag (88.9 mm)
Battery life: up to 20 hours; up to 15 hours with inReach® technology enabled
Memory/history: 16.0 GB
High-sensitivity receiver: Yes
Interface: USB

Maps & Memory
Basemap: yes
Preloaded maps: yes (topographic active)
BirdsEye: Yes, direct to device (no annual subscription required)
Ability to add maps: yes
Accepts data cards: microSD™ card (not included)
Custom POIs (ability to add additional points of interest): yes
Waypoints/favorites/locations: 10000
Routes: 250
Track log: 20,000 points, 250 saved tracks

Sensors
Barometric altimeter: yes
Compass: Yes (tilt-compensated 3-axis)

Outdoor Recreation Features
Area calculation: yes
Automatic routing (turn by turn routing on roads): Yes (with optional mapping for detailed roads)
Custom maps compatible: yes
Hunt/fish calendar: yes
Sun and moon information: yes

Garmin Connect™
Garmin Connect™ compatible (online community where you analyze, categorize and share data): yes