What is an Offline survey?
An Offline survey is a survey that does not require an online conection (internet) to be applied in the field, as the captured data is stored directly in the memory of the mobile device where the survey is applied. The Offline survey therefore has an important utility in market research applications, where non-self-applied questionnaires are to be applied, i.e. through field pollsters. Thus, the offline mobile interview will allow to conduct a face-to-face interview with the subject we are researching (CAPI: Computer Aided Personal Interview). In the past to carry out this type of surveys a laptop, palm or notebook type computer was used, with some program installed that allowed the data entry of the answers by using keyboard, even many researchers used Excel or Word to collect the data in the field, which was subsequently transferred to SPSS or some data processing program.
Typical applications of Offline surveys
The Offline survey is useful when you want to collect data using a force of surveyors in the field and through the use of mobile-cellular technology, whether the interview site is conducted in remote locations where the online-Wifi connection, data network is not available or that the internet signal or data network is not one hundred percent guaranteed. Currently offline surveys are being used in agricultural census studies, electoral surveys in the remote locations, and also in urban centers such as shopping mall, hotels, etc. Thus, the offline survey demonstrates its full potential when the subject to be surveyed is located at remote locations, with no or limited internet connection.
Advantages and disadvantages of the Offline survey
The great advantage offered by the Offline survey is precisely the disconnection mode when conducting the interview. Thus, no internet signal is required for your field application and the data is stored directly into the internal memory of the mobile device. Another advantage is that despite being disconnected, and thanks to the technological advances, it is possible to geolocate the interview point using the device's GPS, take photos, record audio or capture the respondent's signature in situ, doing all this in disconnected form. Later on, when your tablet or cell phone has A Wifi internet signal or data network, you can transfer the collected data as well as photos and audio to a cetral repository, cloud, or remote server. Among the disadvantages of this type of survey is the excessive technological dependence on the technical characteristics of the phones or tablets used, so some elements will become critical during the interview, such as the duration of the battery, the brightness GPS sensitivity and available memory capacity. In addition to the above, it is sometimes difficult to apply the interview in open places with rain or excessive humidity, or where the rates of theft or criminality are high, since the cell phone or tablet might be stolen at certain locations.
Geolocation of the Offline survey
One of the advances made in the design of fourth generation cell phones and tablets is the possibility to collect the geographical location of the interview point, or what is technically referred to as the "Geolocation", i.e. the registering of the coordinates of latitude and longitude - according to international cartographic standards - of the point where the survey has been applied. To be able to collect the geolocation of each point where the survey is applied it is necessary that several conditions be given, 1) First that the device has a physical or virtual GPS, 2) Second that the satellite signal is strong enough to be able to detect it, since sometimes and for atmospheric reasons, the satellite signal is weak, 3) Third that the pollster activates the GPS of the cell phone or tablet at the time of the interview and 4) Fourth that the interview is applied in an appropriate place, since if applied in u n basement or enclosed office, the device will not be able to collect the geolocation.
How to program an off-line survey with Rotator Survey?
How to apply mobile survey offline?
Rotator offers two (2) modes for Mobile surveys: "Open" and "Closed".
In the open survey there is no specific sample (Intentional or probabilistic), but anyone can be surveyed. This mode is ideal for massive surveys to be applied in shopping centers, events, congresses, etc. It is recommended to request the id or ID of the interviewee to avoid being surveyed more than once.
In the closed survey, only people who are part of a database (intentional or probabilistic sample) can respond to it. The software will request an ID to identify the subject to survey and validate that the ID is registered in the participant base. The "closed" mode is ideal for household surveys with probabilistic samples, honeycomb studies to visit on site, store audits, named customer satisfaction surveys. In this mode the user can edit their data once uploaded and there is the possibility to keep the history of each interviewee over time. (Longitudinal study)
The best Apps available to apply Offline CAPI surveys
In the market today there are a large number of mobile application to conduct offline surveys (Apps for offline surveys) and to be applied on mobile devices, these Apps promise to collect the data in a 100% disconnected fashion. We have evaluated many of these Apps and what we have found, is that most of them lack of the many advanced features required by the Market Research Industry, both in the aspect of data validation, programming the flow of the questionnaire, as well as the support of professional features, such as quota control, management of participant databases, voice recording of the interview, real-time supervision of the field surveyors, among many other options that are required for profesionnal application. Here's our sincere assessment of these tools, we recommend that the researcher evaluate at least 5 of these Apps for offline surveys, and select those Apps that best suit the requirements of the Study, which may include: Complex skip logic, multimedia options such as photos and sound recording, unstructured data collection, etc. In addition to all this, it is important that the App for CAPI surveys to be selected has a good tech support and a professional development team to support it. Finally, that the price of the App fits the budget of the research project.
Readings and recommended sites to broaden the discussion