What criteria should you look into when choosing a Mobile Data Collection device ?

This blog post is to help humanitarians planning to buy devices for mobile data collection on their choice, as this can be very important in the success of a project (device adapted to the need, trust in the tool by enumerators …). We hope this blog post will help you save time and money by buying the right devices from the start!

Smartphones vs Tablets

Choosing devices for Mobile Data Collection usually starts with the question of whether to use smartphones or tablets- check out the table below to get a grip on the main advantages of each to help you in your choice:

Advantages of smartphones

Advantages of tablets

Usually less expensive (better features-price ratio)  Lighter to move with (e.g. with neck strap) and to carry (less bulky), particularly for surveys where enumerators spend most of their time standing More discreet (in terms of “image”) Usually better battery life Better camera   Suitable screen size for most types of surveys Better (at the same price) connectivity and geo-location (GPS, GSM, 3G, 4G etc.)

Larger screen size for substantial surveys (easier read and free text entry) or surveys carried out in an office, which can make it a more comfortable tool Less likely to be considered as a GPS in contexts where GPSs are seen as a problem In some contexts, less risk of being stolen as less easy to re-sell

NB: Keep in mind that you will probably be using these for a number of projects over time and therefore the devices that you choose need to be adapted to all of these projects.

Device specifications

When you have made this choice, you can start looking into further criteria that should be considered when purchasing devices. 

Criteria	Details
Battery life	Battery quality should be considered: both for each cycle at the time of purchase but also concerning how long the battery will last over time with a normal usage.Minimum recommended capacity: 2000 mAh, with an “external battery pack” for areas with low charging possibilities.
Display size and keyboard usability	It depends on the type of survey: a survey with lots of “open-ended” questions requires a larger screen size (tablet size potentially) as well as more user-friendly on-screen* keyboardMinimum recommended display size: 4.3” – desirable 5”- NB: keep in mind that too large a screen is also not handy for enumerators!–> User friendliness of the device and its keyboard should be systematically tested (in real situation i.e. standing position, device in one hand, entering open-ended questions…)* To date, no more providers offer models with “physical” slide-out keyboard unfortunately
Weight	It depends on the context but it is a key element for surveys when enumerators are standing all day long while carrying the device in their hand for the device not to be too heavy Maximum recommended weight for “standing face to face” survey mobiles: 200 gr
Ruggedness	It depends on the context but it is a key element for data collection: in the rainy season, in the “bush”, in dusty areas, with motorbikes travels…–> Do not forget to purchase additional accessories in these cases (see below)Some devices are specifically “ruggedized” to be used in hard environment (e.g. IP65 to 68 certification for dust and water resistant design)
Availability (over time) of device series	It is always easier to use a same series/range of devices (installations and trainings are indeed easier to implement as well as remote resolving of problems).–> When purchasing devices, priority must be given to well-know brands, series and models!
Enriched data	GPS accuracy and needed time to find satellites (if applicable)–> Do not forget to test GPS accuracy and needed time to determine the position in  representative places where surveys will be carried out (e.g. without 3G). Be careful, some low budget smartphones have a GPS that does not work without a sim card.Quality and resolution of the camera: Minimum recommended resolution : 5 Mpx with flash (to take pictures inside buildings such as health centers)–> Do not forget to test camera quality for reading barcode and QR code if these are features you think you might use some day!
Connectivity (GSM, 3G…)	Check the compatibility of GSM / GPRS / EDGE / UMTS (3G) frequency bands according to your country* (especially in case of imported devices from HQ or another country) * For more information have a look at: https://en.wikipedia.org/wiki/GSM_frequency_bands and https://en.wikipedia.org/wiki/UMTS_frequency_bands If a GSM connection is required, devices with dual-SIM card can be useful (especially in countries where coverage of telecom operators is uneven or unreliable)
USB connection	Check the connectivity with a USB cable (is essential in contexts with poor wifi/3G connexion)
Standard version of Android OS	To avoid problems when installing apps, it is important to always purchase devices with a well-known version of the operating systemMinimum recommended Android Version: 4.1Make sure of course that the Mobile Data Collection tools that you choose are compatible with the operating system you have chosen!
Memory	Sufficient internal memory and dedicated card slot (to add a microSD card in order for example to download offline background maps, save many pictures…)Minimum recommended internal memory : 8 GB
Chipset and RAM	Minimum recommended RAM: 1 GoMinimum recommended chipset: Quad core 1,2 GHz

 

The recommended figures mentioned are applicable to recent (2015-2016) smartphones or tablets.

Finally, when you have made your choice, to facilitate device management, we recommend that you:

• Systematically test the model at least a couple of days (some providers accept to lend one unit if you plan to purchase a batch of them) to avoid unpleasant surprises (especially before purchasing a large quantity of devices).
• purchase devices per batch of same devices (rather than buying them one by one within different series)

Extra accessories

Beyond the devices themselves, you will need to look into also buying certain accessories that may be needed in your context: 

• Protective case (mandatory in all contexts)
• Glass screen protector (mandatory in all contexts)
• Neck strap (convenient for enumerators for surveys with smartphones, reduced risk of breaking the device)
• USB cables
• Chargers (normal, with car adaptor…)
• Portable charger (power banks for example) to charge devices when reliable power source isn’t available
• External SD cards
• SIM cards if the connexion is good in the country and you would like submissions to be made through 3G rather than Wifi

Hope you found this blog post useful – we wish you good luck on your final choice of device!

This blog post was initially written by CartONG beginning of 2016 for Terre des hommes Lausanne, who then authorised its adaptation and publication on our blog. 

Terre des hommes website: https://www.tdh.ch/fr