Some GPS/GNSS receivers compatible with iPad and iPhone devices

Recently Geneq Inc. announced their new SXBlue Platinum GNSS receiver.

As you know, the accuracy of the work performed using an iOS GPS/GIS app depends on the GPS receiver used. The assisted GPS provided by the iOS devices are not adequate for serious work that are based on accurate locations. External GPS receivers with much better precision abound, but only a limited number of them are compatible with the iOS devices. Following are links to information on some of the external Bluetooth GPS/GNSS receivers that can work with iPad and iPhone devices. Not sureprisingly, higher precision equates to a higher price tag.


Question about the GPS marker

“I also use the program to locate plots to take sample points. With the current cursor on the program you cannot see the points on the background map. Is it possible to change the cursor to be transparent or a cross hair to see the points on the map?”

The GPS marker in the iCMTGIS-series apps serves a few purposes. When GPS is turned on, it indicates your position. If you walk at a brisk pace, the arrow inside the circle will point in the direction you are walking. The arrow in the GPS marker will be a gray color when your speed is very slow (e.g. less than 1 m/s). The arrow will change to a red color when your speed is above 1 m/s. The direction of the arrow indicates your current direction. There is not a way to change this marker symbol.

You could try zooming into the map and enlarging the point symbol size. The GPS marker will stay the same size and will therefore become smaller compared to the background elements.

Is CMT working towards including the OCRS within the ICMT GIS PRO software?

“I am using the EOS Arrow 200 with ICMT GIS PRO on an Ipad. I am wanting to transform my GPS points to the low distortion projections Oregon Coordinate Reference System. I haven’t been able to create a user defined projection to match the OCRS zones. My questions for CMT: Is CMT working towards including the OCRS within the ICMT GIS PRO software? If so would this be available as an update any time soon? If the OCRS zones are not going to be available for ICMT GIS PRO- would the PC GIS PRO software work to build the OCRS zones to download into ICMT GIS PRO?”

Thanks for using our iCMTGIS PRO. This app has the standard LLA, UTM and State Plane coordinate systems built in. Different states and countries (e.g. SWEREF99TM for Sweden, KTM-KUDAMS for Kuwait) might use different projections. You can use the optional PC-GIS X software to create user-defined datums and Transverse Mercator, Mercaator, Oblique Mercator, Lambert Conformal Conic, Albers Equal Area Conic and Double Stereographic projections. After you have copied the user_dat.sys and user_cor.sys files created by PC-GIS X to your iCMTGIS PRO documents folder, iCMTGIS PRO will let you select the user-defined coordinate system to use.

As the OCRS zones refer to the NAD83 datum, you don’t need to create a new datum.

Which product best fits our needs?

“I’m browsing through your website and trying to figure out which product best fits our needs. We run a farming operation that deals with fields of many shapes and sizes. We’re looking for an easy to use solution. Here is our wish list:

1. Non-expensive
2. Integrates with iPhone or iPad
3. Exportable to PC to overlay on Google Maps or other mapping software
4. Sub meter accuracy

Would you be able to point me in the right direction?”

Items 1 and 4 on your wish list are related. The greatest expense you will incur is in the GPS receiver. GPS with sub-meter accuracy cost a lot more than consumer-grade GPS with 2 – 5 m accuracy. The EOS Arrow Gold and the iSXBlue II+ GNSS provide sub-meter accuracy.

Our iCMTGIS III GPS/GIS data collection and mapping app will run on iPhone and iPad devices. It provides the ability to export Feature data as a .kml file that you can upload to Google Earth and Google My Maps. It will also export Feature data in Shapefiles format and DXF file format. Many GIS software provide the ability to import Shapefiles. So does our PC-GIS X mapping software, which will also work with the Job files you created by using iCMTGIS III.

(Farming GPS GIS III provides similar functionality as iCMTGIS III, but it will only run on iPad devices.)

How to determine the direction of a straight line in iCMTGIS PRO?

Line Segment Label

A number of our apps provide a function in the Feature Properties screen for labeling a line segment. In some apps, such as iCMTGIS III and iCMTGIS PRO, after selecting the line segment, you would tap on the “Show Label” tab then mark the check box for “Show Segment label“. In some other apps, such as Wetland – Stakeout and Deed Calls Pro, the “Show Segment label” check box is in the main Feature Properties screen.

With the Angle System set to “Bearing“, the line segment label will show something like SE. This indicates that the line is pointing to southeast.

iCMTGIS III and iCMTGIS PRO also provide the View Deed Calls function. In the Deed Calls screen, the starting node of the active line segment is indicated with a green node. In addition, the bearing of the straight line segment is displayed under Calls.

How to use iCMTGIS PRO to extend a line beyond its end points?

“I have managed to join two nodes and get a straight shape line between them, but how do I do to extend the line on the outside of the nodes?”

There are a few ways to achieve this. Here is a quick way (but not precise): Tap on the existing straight line then select the Insert Node function on the Tools menu. Move the circular Node Tool to the end point of the existing straight line. Tap in the center of the Node Tool. Select “After” then tap on Next step. Now move the Node Tool to a new position, eyeballing the proper bearing, then tap in the center of the Node tool to add the new node. To extend the line in the other direction, select the start point of the line and select “Before” for inserting the new node.

A precise way is as follows: After you have created the initial line based on two existing points, tap on it then select View Deed Calls. Tap on the Calls tab then tap on Edit.

Increase the horizontal distance then tap the Back button.

Confirm to update the Feature. You will see that the Line Feature has been extended in one direction.

Now use the end nodes of the elongated line to create another line in the opposite direction. It will have a different Line ID. You can turn on Sheet View to see the two line records. Select the new line and use the View Deed Calls function to change the distance value. Confirm to update the Feature.

If you don’t confirm to update the Feature, then no change will be made to the original line.

I would create a new Topic (named “Long Line”, for example) into which to put the final long line. This will help reduce confusion when you are staking out in the field. Have this new Topic active and select the correct line when you are doing the Line Stakeout. (You could also delete all the other lines that you will not be using for stakeout.)


How do I label a point shape with its name?

A number of our apps provide the Auto Label function.

Please tap the Topic View icon (the second icon from the right side) then select the Point Topic of interest.

Now tap the Topic Menu icon (the second icon from the left side) then select the Auto Label function and use it to label all the points on the selected Topic layer with the Topic Name and Feature ID.

If you have Attributes defined for the selected Point Topic, you could select those as well for labeling the points.

If you add another Attribute later, then please first delete the existing labels then redo the Auto Label.

If you add a new Feature to the same Topic layer, then please execute the Auto Label again to update the labels.