On your phone, and under your control
This app records only what your study lists, keeps it encrypted on your phone, and starts only after you agree.
Download AppParticeps is Latin for one who takes part in something. What the app records is written to your phone and encrypted there, you see every source your study switched on before you agree, and nothing is collected until you press Start.
The name is not a promise that the study is yours to set. What a study may collect, and how long it runs, are fixed in the signed study file your research team gives you: you can decline the study, or leave it, but you cannot rewrite it. Inside a study you can hold back the sources it marks optional, by not granting the access they ask for; a source it marks required stops the study instead. Nothing that has already left your phone can be taken back.
This page is not your consent document. Where they differ, your consent document and your research team’s answers come first.
Nothing is collected until you press Start
Importing a study file collects nothing. Consent is the third of five steps.
who is asking, why, how long
every source this study switched on
their consent text, the signature, and whether it sends
the Android access it needs
collection begins here
You can leave at any step.
The app follows your phone’s language. The globe at its top right changes it.
Twelve sources exist. Your study uses some of them.
Before you agree, the app lists the ones your study switched on — in the app’s own words, not the research team’s.
App activity
When this app itself is opened and closed
Motion
Movement of the phone, about N times per second or more
Battery state
Battery percentage, charging source, and power-save state
Time context
Time zone, UTC offset, daylight-saving state, and clock changes
Rotation
Rotation of the phone around three axes, about N times per second or more
Ambient light
Illuminance reported by the phone’s ambient-light sensor
Proximity
Raw distance, sensor range, and the phone’s near/far interpretation
Connection type
Whether you are on Wi-Fi or mobile data, and whether it is metered
Data volume
Total bytes your phone sent and received, every T
App and screen use
Which apps open and close, and when the screen turns on, every T
Location
Where the phone is, about every T, after it moves at least D
Keyboard touch
How you touch the keys — position, timing, pressure — inside the research keyboard only
N, T and D come from your study: how often, how long between, how far.
That screen also names selected limits the implementation guarantees. The guide has the complete field table.
Where it goes
Two kinds of study. Your consent screen says which one yours is.
This study does not send data automatically
What it collects stays on this phone until you export it yourself.
This study sends data automatically
Every value in this card is an example. Yours are on your consent screen.
- Sends to
- study.example.org
- How often
- About every 6 hours
- Network
- Wi-Fi only
The encrypted content includes a randomly generated installation code so the research team can tell participants apart after decrypting it. It contains no name and no account.
Automatic sending is part of the study and cannot be switched off on its own.
The receiving server sees when a delivery arrived and how large it was, plus bundle, configuration, digest, and claimed range metadata. It cannot see your installation code or collected content.
What leaves is sealed to a key only the research team holds. The network it crosses cannot open it.
You can export a copy yourself, as often as you like, in either kind of study.
Stop and ask if…
- the fingerprint does not match, or you were never given one
- the study’s contents differ from what you were told
- it asks for more than you expected
- the app did not come from the source your team gave you
- you see Load demo study — a development build, whose keys are public
- anything asks for a password, or to turn off an Android security setting
Advancing research while keeping data safe.