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Mobile Data Collection toolbox

2.1 A few definitions to start with


MDC Frequent terms

Data collection is the process of gathering data through either qualitative or quantitative methods (for example, focus group discussions or surveys, respectively). Data collection occurs after the development of a research approach and the creation of tools to collect data (e.g. survey tools with questions that can accurately measure the research question).

Mobile data collection is the use of mobile technology (mostly smartphones and tablets) to collect data. MDC can be used to improve the quality of data, information, analysis and, therefore, decision-making. It has been used in the humanitarian and development sector since 2008, alongside the widespread availability of Android devices. More specifically, in this toolbox, we refer to it mostly in relation to the collection of “survey-centered” type of data, primarily used for quantitative analysis, rather than geodata (see definition below), that requires dedicated “geo-centered” type of tools.

There is a breadth of tools that can be used, and the tool(s) selected by an organization should be based on a range of factors specific to different needs. Examples of tools for uses that are not too sector specific (with dedicated business processes that go beyond simple data collection…) would be ODK, KoBoToolbox, SurveyCTO, CommCare, ONA, Smap, etc.

For an overview and comparison of different generic MDC tools, please see the Benchmarking of Mobile Data Collection Solutions produced by CartONG, found in section 4.1.1 Choosing and setting up your software.

MDC refers to “Mobile Data Collection” or mobile technology (mostly smartphones and tablets) to collect data.

A survey is a collection of information on a specific topic (most often through a list of questions) from a group of people or a statistical sample of a population.

A form is a data collection tool materialized in the shape of a list of questions.

Geodata collection tools are “geocentered” type of tools to collect geographic data. This concerns tools dedicated to the building of geographic datatabases (where traditional MDC tools are primarily aiming at building attributary data, even if they can have GPS points). Examples of geodata collection are tools such as OSMAnd, QField, Collector for ArcGIS.

Case management

Longitudinal data collection

The deployment of a form is the action of making a newly created form available for data entry. This occurs after the form has been fully developed and you are ready to start testing your form in real conditions or collecting data.

After deployment, in ODK terminology your form can be downloaded as a “blank form” on external devices to start collecting data. If you cannot see your form on the mobile app (for example), make sure you are connected to the correct account. If you are connected to the correct account, your form is likely still in draft mode, and you still therefore need to deploy it on the server.

The submission of a form is sending the data collected (for example on ODK Collect) to the central platform/database (KoBoToolbox), most often through an internet connection or local network. One submission equals one data entry.

A survey manager refers to the person in charge of designing/implementing/following-up the data collection as well as training/managing the enumerators team.

An enumerator refers to the “interviewer” or staff in charge of collecting data in the field using paper or mobile devices.

MDC Form building standards

See section 5.6.7 The XLSForm Cheat Sheet for examples of constraints, repeat, calculations, regex, cascading lists, appearance settings.

Extensible Markup Language (XML) is a language that defines a set of rules for encoding documents in a format that is both human-readable and machine-readable. Commonly used in MDC to code forms that will be used in MDC apps.

XForms is an XML format used for defining forms. It is fully compatible with the KoBoToolbox form builder.

XLSForm is a form standard that can be used directly in Excel to simplify the creation of forms. The XLSForm is then converted to an XForm when the form is put on KoBoToolbox (although you as user don’t see this!)

To go further, see this section.

In form design, the terms validation criteria and constraint refer to the same function, the purpose of which is to constrain the input of responses to a certain format in order to improve the quality of the data by making it uniform.

For more information, see section 5.6.4 Validation criteria and CartONG XLSForm Cheat sheet for examples.

A skip logic function is available in a question or a group setting so that only the appropriate questions are displayed, which means you can follow a certain path, skipping questions based on certain answers. For example, you might only wish to have certain questions appear based on the consent of the respondent, his or her age, gender, localisation etc.

For more information, see section 5.6.3 Skip logic.

Mandatory questions refer to survey questions for which answers are mandatory. These force enumerators to fill in an answer before proceeding to the next question (source: Oxfam mobile survey toolkit). It is often materialized by an asterisk.

To go further, see this section.

Cascading lists refers to a form construction that permit to filter possible answer for a question depending on the input of the previous questions. See CartONG XLSForm Cheat sheet for more informations, tutorials and examples.


Regex (or regular expression) refers to the specific, standard textual syntax for representing patterns that matching text or integers need to conform to (source: Wikipedia). It is a type of constraint often used for the capturing of phone numbers, identifiers or emails. You can see some example in the sheet “constraint” of CartONG XLSForm Cheat sheet.

To know more about regex, you can see this section.

P-codes for Place codes or Position codes are unique geographic identification codes that are often used to designate administrative unit (district, region, municipality, state, etc.).

To know more about P-codes, you can see this section.

Unique identifier

To go further, see this section.

Humanitarian Exchange Language (HXL) is a standard for classification and naming of data in the sector. It allows to have a common understanding of data by standardizing it. It avoids wasted effort on manually copying, preparing, validating, and cleaning data which can be very useful for data sharing. The tag and the attribute system is simple, allows a good level of precision and helps avoid confusion over what the data actually means. Therefore, it helps overthrow the language barriers on datasets.

To know more, see this section.

Data Protection

Please refer to the responsible data toolbox.

User right/access right

Software and Hardware

Hardware refers to machines, wiring, and other physical components of a computer or other electronic system (source: The Easy Guide to Mobile Data Collection, School of Data).


Server refers to computer program or machine that waits for requests from other machines or software (clients) and responds to them (source: The Easy Guide to Mobile Data Collection, School of Data).

For example, in the MDC world, the KoBoToolbox or ODK Central online interface (“form builder”) where you can conceive your form and view survey submissions are servers.

To go further, see this section.


Open Data Kit (ODK) is an open-source set of tools for Mobile Data Collection. It is one of the most popular MDC solutions and is the basis for many other free or paying tools of the MDC world. Find out more about the set of tools here or the history of the project by listening to this podcast. When the term is used on a day-to-day basis, it often refers to widely used ODK mobile app that can itself connect to different MDC servers (such as ODK Central, KoBoToolbox…).

ODK Central is a free (if one installs on one’s own server) and open source server for Mobile Data Collection maintained by the core ODK development team (replacing the widely used “ODK Aggregate”). Find out more here.

KoBoToolbox is a free and open-source set of tools for Mobile Data Collection from the ODK world. Developed by the Harvard Humanitarian Initiative, it is in particular made available for humanitarian organisations by UNOCHA. Find out more and choose the server you should access here.

A web form is an online page that allows for user input. It mimics a paper document or form, where users fill out particular fields.

Enketo Web form is an open-source web application used by many MDC platforms (in particular those of the ODK “world”) to enter data directly through a web browser rather than an app. It is therefore often used to enter data through a computer interface, through it can also be used on a mobile device when one prefers to use a web browser than an app. Find out more here.

Power BI is a business analytics service provided by Microsoft. It provides interactive visualizations with self-service business intelligence capabilities, where end users can create reports and dashboards by themselves, without requiring too specialized a background. Many NGOs and international organisations use Power Bi offline or online dashboards to visualize or analyse MDC data.

Other business intelligence software is also used in the sector, such as Qlik or Tableau.

IMEI number (International Mobile Equipment Identit) is the worldwide unique 15-digit code assigned to individual mobile devices (source : Oxfam mobile survey toolkit).