Clew: Navigation App Review

Clew is an iOS app that records a user's path and then guides the user back to his starting point. Clew was created to help travelers who are visually impaired to remember a location such as returning to a seat in a room. Designed to work indoors, Clew uses augmented reality to record landmarks along your route. Clew is available for free in the App Store.

How to Use Clew

Hold your phone upright in front of you with the camera pointing straight ahead. Press the record button, then walk your route. In the Clew video, the developers recommend that the user first travel and record the route using human guide. Press Stop Recording at the end of the route. When ready to return, Press Return. Wait for Clew to convert the information. Clew will then provide verbal, haptic and visual feedback as the user reverses his route. Visually, the screen shows an image of the next route segment with a red pin indicating where to go. (Clew calls the pin 'Crumb Indicator'.) If the user veers off the path, the red pin disappears off the edge of the screen. When walking along the desired path, a clicking sound is heard; the clicking sound stops to indicate when the traveler has veered. A whistle tone indicates a turn; the app also verbally announces which way to turn. The route is available until the app is closed using the app switcher. According to the website, Clew works best with short routes.

The developers of Clew are asking users to provide feedback.

The video below provides information about Clew.

Editor Comments

NOTE: Clew is used in addition to a cane or dog guide; Clew does not provide any protection for obstacles/surface changes and is intended only to give reverse route navigation information!

The app is simple to use, with only one or two buttons on the bottom center of the screen; these buttons appear as needed. Example: The Start Recording button appears initially which is replaced by the Stop Recording button. After the recording is stopped, the Navigation and Pause buttons appear.

I recorded a route to a bathroom and then used Clew to return to my seat in another room. This route included hallways, multiple turns and stairs. In another route, I recorded using Clew to go from a desk in a classroom, traveling in several hallways and turns, traveling outside and going down a spiral staircase. Both of these routes were in uncluttered and quiet hallways.

NOTE: A route can only be traveled one time. When I went back to the restroom and wanted to reverse the route back to my seat the second time, Clew indicated that I had "arrived" at the restroom and I did not have the option of reversing the route back to my seat again.

For best results, use Clew in uncluttered environments; moving pedestrians may impact Clue's accuracy. When recording your route, make good 45 degree turns. Accuracy may improve when you exaggerate your turn by slowing down slightly and making a military-style 45 degree turn. Clew is most accurate when traveling in straight lines and 45 degree turns. Moving in a straight diagonal line through open space worked well during one route; however, when transitioning from a wide hallway to a narrow hallway, Clew did not indicate where the narrow hallway was (and without good O&M skills, I would have run into the wall!) When ascending a spiral staircase, Clew periodically announced to turn right and go upstairs.

Clew's website shows shows a Customize Settings Screen which allows users to choose options such as unit of measurement, Crumb color, toggle on/off features, etc. However, when reviewing the app, I could not find the customized settings page.

O&M Perspective

As an Orientation and Mobility Specialist, my goal is to teach students how to use environmental clues and landmarks, mental mapping skills, and other standard O&M skills. Once learned, these skills can be transferred to any environment. Ideally, students should have strong O&M skills and should not need the assistance of an app to reverse a route. However, every traveler is unique and there may be some travelers - especially those who are in the process of learning good O&M skills - who may benefit from Clew to help retrace steps. I would caution users and O&Ms that this app should be used as a training tool and travelers should not become dependent on it.

As a training tool, Clew does a wonderful job of breaking a route into segments. As an O&M working predominantly with preschool and K12 students, I intentionally teach students to break a route into chunks. Students often are overwhelmed with the amount of sounds and landmarks in the environment and are easily distracted or perseverate by things along a route. This app does a great job of filtering out the extra information and focusing on the truly important pieces of the route - the next turn or the next major landmark such as traveling up/down stairs. When working with O&M students, I use the term "next decision-making landmark" paired with what he is to do at that landmark; this helps the students to focus on the big picture and to not get lost in all the details! Typically, the "next decision-making landmark" is an intersection and the student needs to name which way he is to turn. If the next decision-making landmark is a staircase, then the student has to also name whether he is going to ascend or descend those stairs. 

I am already buzzing with ideas on how to use Clew as a tool to teach breaking routes into segments and how to focus on the next decision-making landmark. I would like to be able to turn off the announcements and have just the whistle tone indicating a turn (without giving information about which way to turn). This would be a good "training wheels step" for users who might need some prompt but who should know the general direction he needs to travel and should be anticipating his route.I can also see how Clew would be a fun tool to reinforce reverse route concepts! How will YOU use Clew?


  • The ability to save, name and use a recorded route again. (Currently a Clew route can only be traveled one time.)
  • The ability to save multiple routes.
  • The ability to label (name) the hallways/intersections, as this will help establish a mental map.
  • Ability for Clew to announce the next decision-making landmark as the traveler begins that segment of the route, so that the traveler can set in his mind what he is looking for (this might be a settings feature that can be turned on/off).