7DS Tools: PDF, Image & Calc

Fifty-nine small tools that do one job each, in one app that stays out of your way.

Most tool apps are a thin shell around a website, so nothing works on a weak connection. This one is built the other way round: 49 of the 59 tools run entirely on your phone. No spinner, no "check your connection", no waiting. Open the app in a lift, on a train, or with one bar of signal, and the calculators, converters, text tools and image editing all still work.

ORGANISED AS STUDIOS, NOT A LIST OF 59 ICONS

Tools are grouped into focused hubs, so you land where your task lives:

• PDF Studio — merge, split, rotate, compress, lock and unlock PDFs, and build a PDF from your own photos
• Image Studio — compress, resize, crop, rotate and convert images, entirely on your device
• Finance Studio — EMI, SIP, FD, RD, GST, interest, discount, loan prepayment, in-hand salary, live currency conversion and gold and silver prices
• Developer Studio — JWT decoder, UUID generator, regex tester, cron parser, timestamp converter, URL encode/decode, colour picker and password generator
• Writing Studio — case converter, word and character counters, JSON and SQL formatters, Base64, hash generator, text diff, slugify and Lorem Ipsum
• Student Studio — percentage, CGPA and age calculators
• Business Studio — SEO checker, YouTube channel audit, UTM link builder, hashtag generator
• Daily Utilities — QR code generator, unit converter, BMI and date calculators
• Content Studio — script read time, post character counter and aspect ratio guide
• Fashion Studio — size chart converter, fabric calculator and stitching cost estimator

WHICH TOOLS NEED THE INTERNET

Ten of them, and they are marked with a cloud icon so you know before you tap: the six PDF tools, the currency converter, gold and silver prices, the SEO checker and the YouTube channel audit. Everything else works with aeroplane mode on.

WHAT WE DON'T DO WITH YOUR DATA

• Your photos never leave your phone. Every image tool runs on the device itself.
• A file you send to a PDF tool is deleted as soon as your result is ready — the document you sent and the result we made. We never read, index or store what is in it.
• Search runs on your phone. We record how long your search was and whether it found anything, never the words you typed.
• We never store the values you type. We know the EMI calculator was used. We do not know your loan amount.
• A generated password and a BMI result stay on your device and cannot be saved to history.
• No ads, and no data sold or shared with advertisers.

NO ACCOUNT REQUIRED

The app works fully the moment you install it. It creates an anonymous account so favourites survive a reinstall — no name, email or phone number attached. Signing in with Google is optional, and only needed if you want favourites on a second device. You can delete your account and everything with it from Profile, in one tap.

BUILT FOR SMALL SCREENS AND OLD PHONES

About 11 MB to install — most single-purpose tool apps are larger than that on their own. No background services, no notifications, no permissions requested at install. The app asks for your photos only at the moment you pick one, and never reads anything in the background.

FREE

All 59 tools, with no paywall, no trial and no locked features.

Make in India by Seven Digital Services.

Questions or a tool you wish existed: contact@7ds.in
Privacy policy: https://www.7ds.in/privacy