The wiSamples App for Sample Collection

This iOS app has been developed to assist our own research group and others in collecting standardized metadata for water isotope samples. It takes advantage of structured data interfaces and the sensors embedded in our now-ubiquitous pocket computers to make metadata collection easier and more robust.

User's Guide


Platform and Security

Can I use the app on my Android device?

No. Currently we only support an iOS version.

Can I use the app on my iPad?

Absolutely. wiSamples has been tested on most current iPad versions and should work on yours. Keep in mind that iPads without cellular chips do not have internal GPS capabilities. These devices can provide coarse location information when connected to WiFi, but in many or most cases you will have to manually select and position sampling sites in the map interface. Also remember that you will need to pack map and site data while you have a data connection if you intend to use these devices in the field.

Who else sees the data I'm collecting with the app?

No one. All the information is stored locally on your device and you control who receives the data upon export. That said, wiSamples is designed so that the metadata you collect can be seamlessly imported into the wiDB, so if you are interested in sharing your results with the research community this is easy to do. You control if and when that happens.

Can I share information between devices or back up my metadata in the cloud?

Not currently. The current release of the app stores all data locally. To make sure you don't lose your metadata if your device is lost or damage, we recommend that you periodically export your projects so you have a back-up copy of this information.

Sample Information

How do I pick a good prefix for my sample and site IDs?

Ideally you want your IDs to be unique, be as meaningful as possible, and be easy to write down on your sample bottles. Unfortunately, it's nearly impossible to achieve all three goals. The default ID scheme used here attempts to strike a balance, ensuring unique IDs within a project and allowing you to choose a prefix that embeds some information useful to you. We recommend choosing something that includes information that, for example, could help you easily identify which samples on the lab bench are associated with which project, but is short enough to make written records manageable.

Why doesn't the app support barcode IDs?

We'd like to include barcode support in a future release, but it's not available yet. If you are an iOS developer and are interested in helping add new functionality please feel free to get in touch!

Why don't I see my sample type in the selector list?

In order to achieve standardization that's necessary to make large databases such as the wiDB effective we have adopted an enforced vocabulary for some metadata fields, such as sample Type. We think the list provided covers most types of samples being measured today, and additional details can be recorded in the Sample Comments field. If you find the list woefully inadequate for your purposes, please feel free to contact us and make your case. We may be able to expand the list in future updates.

Site Information

How do I edit information for an existing site?

It is not possible to edit metadata for existing sites, since other samples, either from your own projects or those of others, may also be associated with these sites. When you associate your sample with an existing site, you are linking it to an established sampling location and site information. If you need to add customized metadata contextualizing a site for your own purposes, you should add a new site.

Should I define a new site or associate my sample with an existing one?

In general, unless you need to add custom metadata, it is best to associate your sample with an existing site if one exists at your sampling location. In addition to reducing redundancy, this makes it much easier for you or someone else to link your data with other measurements that may have been made at the same location.

How far apart do two sampling locations need to be to justify making a new site?

The answer really involves a judgement call on your part, and we suggest you consider the following factors:

  • Are the locations distinct in an intentional, meaningful sense? If you are effectively re-sampling the same location, but are unsure of whether you returned to the exact site, or had to change locations by some small distance due to practical constraints, you might choose to use the existing site. On the other hand, if you have a sampling program that involves repeat sampling from the right and left banks of a stream, for example, you might want to define these as two different sites.
  • Are the locations different beyond the resolution of the location data? The GPS receivers in our devices are amazingly good, but still are precise only to within several meters under ideal conditions. If you are sampling two locations that are a meter apart, establishing multiple sites may not be warranted. Instead, you could add Sample Comments indicating the relative position of your samples.
  • Can I add a photo of my sampling site?

    Unfortunately, we don't currently support links between wiSamples records and photos. We think this would be a cool addition, too. Watch for future updates. In the mean time you can always tag your photos with a Site ID!

    Pack and Export

    Why is my exported metadata divided among several files?

    Although it may not be the way you're used to working with your data, the structure used here incorporates best practices for data management by dividing data into tables that store distinct types of information. This reduces redundancy, providing an efficient model for storing and accessing the information and eliminating ambiguity that results if the same piece of information is recorded more than once. The information in the tables is linked by the Site_ID and Project_ID fields, and can be easily combined using simple database functions such as lookup in Excel and match in R.

    Can I export my metadata directly to the wiDB?

    Not at this time. If you want your sample metadata to be added to the wiDB you will need to email a copy of these files to us. We will do a quick quality check and then complete the upload.

    If you guys upload the metadata, how do my analytical results get added to the wiDB?

    There are two ways this can happen:

  • If you have your water isotope samples analyzed at the University of Utah SIRFER laboratory (and in the future potentially other participating labs), just send along your metadata files instead of a traditional sample list when you submit your samples. We will upload your metadata and analytical results as part of our regular analytical service. On submission, please let us know if you'd like your results to remain proprietary, in which case they will be entered in the wiDB and available for later release but will not be accessible to the public until you tell us to release them.
  • If you analyze your own samples or have the work done elsewhere, all we need is a report of the results in the format found on the Water_Isotope_Data tab of the wiDB Data Submission Template. This can be sent to us along with a copy of the metadata tables at whatever time you are ready to archive your results in the database.

  • Isoscapes: Understanding Movement, Pattern, and Process on Earth Through Isotope Mapping
    (ed. West, Bowen, Dawson and Tu; Springer)
    All material copyright 2003-2022 by Gabriel Bowen | Supported by CHPC at the University of Utah
    Contact me: