Welcome to Summa Calculator — a fast calculator, optional AI voice input,
and practical everyday finance tools in one app. This guide explains how to get the most
from Summa. For quick answers, jump to Frequently asked questions.
1. Getting started
From Home, tap any tool card to open it. Use the menu (☰) or drawer from
calculator screens to switch between tools, open Settings, or go Premium.
Calculator — tap numbers, then an operator (+, −, ×, ÷), then =.
Scan — photograph a price or total (or pick a photo). The amount fills the calculator display; history and ANS stay unchanged.
History — open from the toolbar to review or reuse past results.
Settings — voice, currency, Premium, privacy, and app preferences.
2. Calculator basics
Keypad
C clears the current input.
⌫ (backspace) removes the last character.
% supports common percentage calculations.
± changes the sign of the current value.
( ) groups expressions; scientific functions are available in scientific mode.
Scan amount
Tap Scan next to the Use in row. Photograph a price or total, or pick a
photo. If several numbers are found, choose one. The amount fills the display only —
it does not add a history row or change ANS. Camera permission is requested the first
time you scan; photos stay on the device.
Scientific mode
Switch to scientific mode from the calculator toolbar for functions such as square root,
trigonometry, powers, and constants. Results follow standard operator precedence.
Tip: After you press =, the result can be sent to Currency,
Tip, or other tools using the Use in row below the display.
3. Voice input (Premium)
Voice and AI interpretation are Premium features. When you subscribe or start
an eligible free trial, the microphone button appears on supported calculators and tools.
Tap and hold the mic, speak naturally, then release when finished.
Examples: “25 plus 13”, “120 divided by 6”, “18 percent of 450”.
Microphone permission is requested only when you first use voice.
In Settings → Voice, turn spoken feedback on or off and adjust speed.
Summa does not listen in the background. Audio capture stops when you release the mic button.
See our Privacy Policy for how voice data is handled.
4. Tools at a glance
Tool
What it does
Calculator
Basic and scientific arithmetic with history.
Currency
Convert amounts using near real-time reference rates.
Tip
Split bills and calculate tips.
Budget
Track income and spending categories.
Unit converter
Length, weight, temperature, and more.
Fuel trip
Estimate fuel for a journey — from places, or from a fill-up.
Energy estimator
Track electricity usage and cost.
Daily snapshot
Quick view of your day-to-day finances.
Travel planner
Plan trips with budgets, wallets, and scenarios (Premium scenarios).
Open Fuel Trip from the menu. Enter distance, efficiency, and fuel price
to see estimated fuel and cost. You can type every field yourself.
Distance pin — type From and To, pick a suggestion (city and country),
then Use this distance. That fills one-way kilometres or miles.
Turn on Round trip if you need both ways.
Efficiency pump — enter fuel used and distance driven from a real
fill-up. Summa fills Efficiency in the unit you selected (km/L, L/100km, or mpg).
Place names are sent to OpenStreetMap to measure the road — not GPS. See
Privacy Policy.
6. Currency converter
Select From and To currencies, enter an amount, and Summa
shows the converted result using rates updated in near real time. An internet connection is
required for live rates.
Reference rates only. Converted amounts are for information. Rates may differ
from those offered by banks, card issuers, or money-transfer services. Fees, taxes, commissions,
and other charges are not included.
You can save favourite currency pairs, share results, and store conversion presets
(Premium raises saved-setup limits). Open the overflow menu (⋮) →
Exchange rate information for the full disclaimer.
7. History, favourites & saved setups
History
Calculation history is stored on your device. Free users have entry limits;
Premium unlocks unlimited history, search, export, and sharing in supported tools.
Saved setups
Tools such as Currency, Tip, Fuel, and Unit converter let you save named presets for quick
reuse. Manage them from each tool’s overflow menu.
Drawer favourites
Pin your most-used tools in the navigation drawer. Premium removes favourites limits.
8. Floating calculator bubble
From Home, turn on the floating bubble to keep a mini calculator visible
while you use other apps. Android may ask you to allow display over other apps
— Summa uses this permission only for the bubble.
9. Ads & Premium
The free app includes banner ads on some screens. Summa Premium is an optional
subscription that removes ads and unlocks:
AI voice on calculators and tools
Unlimited history, search, and export
Unlimited saved setups and drawer favourites
Travel scenarios and unified memory search
Weekly usage insights on Home
Upgrade from Settings → Premium or the drawer. To restore on a new device,
use Settings → Restore purchases with the same Google Play account.
Billing, trials, and cancellation are handled by Google Play — see our
Premium Subscription Terms.
10. Privacy & permissions
Summa is designed to keep your data on your device:
Microphone — Premium voice only, while you hold the mic.
Camera — Scan amount only. Text is read on the device; photos are not uploaded. Requested only when you tap Scan.
Fuel Trip From/To — place names you type (not GPS) are sent to OpenStreetMap to measure the road. You can type the distance instead.
Notifications — optional reminders you enable (budget, daily snapshot).
Internet — ads, analytics, currency rates, optional Fuel Trip place/road lookup, and Premium cloud voice processing.
Display over other apps — optional floating bubble only.
Yes. Summa is free with banner ads on some screens. Premium is optional — it removes ads,
unlocks AI voice, and raises limits on history, saved setups, favourites, and more.
How does voice input work?
Voice and AI interpretation are Premium features. Tap and hold the mic, speak naturally
(for example, “25 plus 13”), then release. Microphone access is requested only when you
first use voice.
Why don't currency rates match my bank?
We show near real-time reference rates. Banks, card networks, and transfer services often
apply their own rates, fees, and margins. Converted amounts do not include taxes or other
charges.
Where is my calculation history stored?
On your device. Premium unlocks larger history, search, export, and sharing in supported tools.
How do I restore Premium on a new device?
Open Settings → Restore purchases while signed in to Google Play with the same account you
used to subscribe.
Does Summa need internet?
Most tools work offline. Currency conversion and live rate updates require a connection.
Premium voice may need internet for speech recognition and AI processing.
How do I cancel Premium?
In Google Play: Profile → Payments & subscriptions → Subscriptions → Summa Premium.
You keep access until the current billing period ends.
What is the floating calculator bubble?
A mini calculator that stays on screen over other apps. Enable it from Home. Android may
ask for display-over-apps permission — used only for this feature.
12. Contact support
Still need help? Contact SmartTools support from the app
(Settings → Contact us) or email us directly: csmarttools@gmail.com
When contacting us, include your device model, Android version, and a short description of
the issue. We aim to respond as soon as possible.