What it does

The contact page shows everything at once — numbers, emails, company, address, birthdays, notes, a ringtone of its own — with call and message on every line
That person's call history sits on the same page: every call, its direction, when, how long, one-tap redial
Search by name or number, an A–Z rail down the edge so 400 contacts are one drag away, and a keypad tab it can open on
Add, edit and delete contacts, copy a number, share a contact; a contact synced by another app is shown as read-only rather than broken
Dual SIM in one tap: the chip on the keypad switches cards and the call goes out on that one
Set it as your phone app and it takes the calls: its own call screen with hold, its missed-call notification with Call back, and decline-with-a-message from replies you write yourself
Blocked numbers, kept in the phone's own block list
Six themes and six launcher icons, from Settings

No internet permission. It reads the phone's own contacts and call log, places the call on the SIM you picked, and holds no socket that could carry any of it away.

What it can reach

This is the whole list. Android prints the same thing under Settings › Apps › Permissions once the app is on your phone, and it was not written by us — check one against the other.

Contacts	The list you are looking at; it is read from the phone's own contact store, not a copy of ours
Call log	The history under each contact, and the Recents tab
Make and answer calls	What a phone app does; the call screen is the app's own
Phone state and SIM	Which of your two cards carries the call you are placing
Notifications	Missed calls, and the call you are on
Internet	Absent. The permission does not exist in this app

Android 8.0 and up. Bought once, yours to keep: no account to make, no subscription, and no upgrade screen inside the app — the licence you buy unlocks it and every version after it.

Against the apps it replaces

Samsung and Google split the job across two apps and a Google account; here contacts, dialler and call history are one screen with nothing to sign into
Google Phone's caller ID and spam warnings work by sending every incoming number to Google. This app cannot: it has no network permission
The call history of a person is on their contact page, where you look for it — not in a separate log you filter by hand
Dual-SIM choice is a chip on the keypad, not a prompt on every call

Compared with Samsung Phone and Contacts, Google Phone, Fossify Phone.