Testing

vCard sources

Body Corp, containing two person kind of contacts (Arnold Alpha, Bert Beta) and one organization kind of contact (Body Corp)
Cold Temp, containing one person kind of contact (Cecil Celcius)

Use the HTTP proxy in Support/rproxy.rb to test the app with HTTP basic authentication and HTTP caching. Usage:

$ make rproxy
Proxy URL:            https://dl.dropboxusercontent.com/u/1404049/
Basic auth:           uname:passwd
Delete cache headers: false

This starts the proxy with default configuration. Use http://localhost:8080/u/1404049/vcards/bodycorp.vcf as the vCard URL in the app.

Use environment variables for configuration:

RPROXY_URL=$url for the URL to proxy
RPROXY_BASIC_AUTH=$username:$password for the username and password for HTTP basic auth, use empty value to disable
RPROXY_DELETE_CACHE_HEADERS=true|false to enable deletion of HTTP cache headers from responses

Import default sources, see imported contacts in the Contacts app
Try HTTP caching effect when importing vCard source again. If the remote supports HTTP cache mechanism, the app shouldn't download the remote file again. If the remote does not support HTTP caching, the app downloads the remote file on every import.
Add, update, and remove vCard sources
Start import, select vCard source to see its details. Import should proceed in the background.
Reorder and remove vCard sources while import is in progress
Try how GUI reacts to

Rotating to different device orientations
Text sizes while the app is running (set via Settings → General → Accessibility → Larger Text)
Different devices (iPhone 4S, iPhone 6 Plus, iPad Air 2)

Disallow app's access to Contacts (required for the app's Import action, set via Settings → vCard Turbo → Contacts)
Try validations