Contacts app for Android with standalone database ad-free open source

Question

Many apps silently sniff contacts data from smartphones, as far as I am told. I'm looking for an app for Android that stored contacts as standalone local DB or file, with editing, import/export from csv, calling feature and optionally ability to copy contacts between its storage and standard one. Preferably ad-free.

Added: preferably open source course who knows what app for those who are pro-security does under the hood.

Answer 1

Open Contacts is available at F-Droid and should meet your requirements:

• Android App: Yes.
• stored contacts as standalone local DB or file: Yes, and only there.
• ads-free: Yes.
• with editing: I'd assume so (not tested the app myself)
• import/export from csv: Well, isn't the VCard format much better suited for contacts? This app uses VCard format for import/export – the same format used by the stock contacts app, so you can transfer your contacts over.
• calling feature: Yes, even matches incoming calls to show the name of the caller.
• ability to copy contacts between its storage and standard one: Yes, via import/export in VCard format (see above)
• open source: Yes

Quoting the app description:

Even though we are not having any problem sharing our mobile number with all third parties, people in our phone book might have. We should not be sharing their contact information online. So, keep your contacts safe in a different database. This app saves contacts in its own database seperate from android contacts. This way no other app would be able to access contacts. Can be used in place of your default phone(dialer) app. It can import contacts from vCard files. So we can export Android contacts and import into this app. Maintains call log as well coz Android call log app would not be able to show name of contact. Also shows the person's name upon recieving call

Enjoy: this almost perfectly matches your requirements 😃