Callcalc: Smart Calculator, developed by MobLap, helps users perform quick numerical tasks during phone conversations. It surfaces a movable floating calculator over the calling screen and can launch automatically at call start or immediately after a call ends, so users avoid switching apps mid-conversation. It also saves calculation history, supports basic arithmetic, offers theme customization, and operates offline with minimal system impact and resizable overlay controls. Sales reps, logistics coordinators, and advisors who handle figures during calls benefit from immediate calculations and record-keeping.

Callcalc keeps arithmetic accessible without leaving the call screen

Callcalc provides a movable overlay that appears over the calling interface so users can perform addition, subtraction, multiplication, and division without switching applications. The tool offers a post-call trigger that launches the calculator immediately after a call ends and a calculation history that saves recent entries for later review. These behaviors address the core problem of capturing and computing numbers discussed during live conversations.

It runs in the background with a small performance footprint

The app is described as working while calls proceed, operating offline and designed to have minimal impact on system performance. It requires Android 5.0 or higher and the runtime permission to draw over other apps, plus phone-state detection to detect call start and end events. That permission model lets the calculator appear automatically while keeping network traffic unnecessary for core functions.

It is accessible for non-technical users but requires permission awareness

The interface uses a movable, resizable window that avoids blocking essential call controls, which helps non-technical users perform quick tasks. Theme customization and a simple basic-operations layout reduce the learning curve. Users should note the app requests overlay and call-state access; those permissions are necessary for the in-call triggers and floating behavior, so some familiarity with app permissions is useful before enabling automatic modes.

Callcalc is practical for professionals who need fast, in-call arithmetic

Callcalc is a pragmatic option for professionals who frequently require quick calculations during voice interactions, provided they accept granting overlay and call-state permissions. As a practical tip, keep history retention minimal if you handle sensitive numbers and position the floating window to a corner before important calls. The app performs reliably for users who need immediate numeric handling while speaking on a mobile device.