SendPin
Send a pin from Maps to Karoo
Only for iPhone
Free · Designed for iPhone. Not verified for macOS.
iPhone
Look up a location on your phone, send it to your Karoo and let it do the navigating.
SendPin is a companion app for the Hammerhead Karoo, a cycling GPS computer. It
sends a destination from the iPhone to the Karoo over Bluetooth Low Energy: the
iPhone advertises a custom BLE service holding the destination in a GATT
characteristic, and a Karoo-side extension — built on Hammerhead's own
officially supported third-party extension framework (karoo-ext) — reads it
and hands the coordinates to the Karoo's built-in navigation.
PURPOSE AND TARGET AUDIENCE
The audience is cyclists who own a Hammerhead Karoo and want to search for a
destination using their phone rather than the Karoo's own limited on-device
search and keyboard.
The problem: cyclists often want to find somewhere to go — a café, a shop, a
place a friend recommended — while already out riding, especially somewhere
unfamiliar. Doing that safely is hard: checking a phone one-handed while
riding is dangerous, and a bike computer's small keyboard and limited search
make it a poor tool to look something up in the moment.
The value: SendPin makes it easy to search for a destination on the iPhone —
Apple Maps reviews, a larger screen, or simply opening a pin a friend sent
over iMessage — and then navigate to it on the bike computer, instead of
riding one-handed with the phone out to check it.
SETUP, ACCESS, AND WHAT'S VERIFIABLE WITHOUT A KAROO
No login, account, or credentials of any kind — there is nothing to provision
for review.
1. Install SendPin.
2. Find a place in Apple Maps, tap Share, select SendPin.
3. A card appears over Maps and begins advertising the destination over
Bluetooth Low Energy immediately. This much is fully testable without any
additional hardware:
• The empty state and welcome screen explain the full flow in plain text.
• After about 25 seconds with nothing reading it, the card reports that
nothing picked up the destination — the expected result with no Karoo
present.
• The shared place is saved in the app's history. Opening SendPin and
tapping it resends the same destination the same way, and the live
Bluetooth log is visible under Settings → Connection details.
4. A Hammerhead Karoo running the free, open-source SendPin extension
receives it within about two seconds and shows the pin, ready to
navigate. This half requires hardware Apple does not have, which is what
the attached recording demonstrates.
SCREEN RECORDING
A screen recording is attached demonstrating the app's functionality, starting
with launching the app. The only part of the flow it cannot show is the Karoo
itself — a separate physical device — receiving the location and confirming
the pin was picked up, since that happens on hardware outside the iPhone. The
recording does show the iPhone side completing successfully: the destination
is picked up and sent.
• No account registration, login, or account deletion — the app has no
accounts of any kind.
• No user-generated content.
• No paid content or features — the app is free with no in-app purchases.
EXTERNAL SERVICES, TOOLS, OR PLATFORMS USED
None. SendPin makes no network requests of any kind — no analytics, no crash
reporting, no authentication service, no payment processor, no AI service, no
data provider, no backend of any kind. The only communication it performs is a
direct, local Bluetooth Low Energy transmission from the iPhone to a Karoo
within a few metres — the same category of connection a power meter or heart
rate strap uses. There is nothing external to list.
REGIONAL DIFFERENCES
None. There is no server-side component, no geofencing, no region-specific
content or feature gating anywhere in the app. It functions identically in
every region.
REGULATED INDUSTRY OR PROTECTED THIRD-PARTY MATERIAL
Not applicable. SendPin does not operate in a regulated industry and includes
no protected or licensed third-party material. It uses only Apple's own
frameworks (MapKit, CoreBluetooth) and displays only content the user has
personally selected in Apple Maps.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
The developer, ALBERT JIA-JIE FOO, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- ALBERT JIA-JIE FOO
- Size
- 3.6 MB
- Category
- Health & Fitness
- Compatibility
Requires iOS 17.0 or later.
- iPhone
Requires iOS 17.0 or later. - Mac
Requires macOS 14.0 or later and a Mac with Apple M1 chip or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © 2026 Albert Foo