Security reviews for web apps, APIs, authentication, and deployment surfaces.
- OWASP top-10 review
- Auth + API tests
- Findings report + fixes
We build and secure the software your organisation runs on
Application security and software development for schools, universities and growing businesses. Six years of work in Zimbabwe, South Africa, Russia and the USA.
Invalcre (Private) LimitedEst. 2022Zimbabwe ↔ South Africa ↔ Russia ↔ USAWeb Pentesting from $1,000Mobile App Development from $2,000Backend Development from $1,500Web Apps / Full Stack from $1,000WhatsApp Bots from $500Landing Pages from $500Consulting from $200Larger organisation? Book a call
40+projects shipped
10+clients
6years building software
4countries: Zimbabwe, South Africa, Russia, USA
01Services
Build and secure, from $200
Every price is a starting point. We scope and quote after a short call.
01Mobile App DevelopmentCross-platform mobile apps for Android and iOS, built for launch and future scale.$2,000to start02WhatsApp BotsCustomer support, lead capture, booking, school, and business workflows over WhatsApp.$500to start03Backend DevelopmentSecure, scalable APIs, databases, admin tools, documentation, and integrations.$1,500to start04Landing PagesFast, SEO-ready launch pages for products, schools, businesses, and campaigns.$500to start05Web Apps / Full StackComplete dashboards, portals, SaaS products, and custom business applications.$1,000to start
02Security
Apps break in four places
We test all four: the sign-in, the API, the data and who can reach it. Six years of building apps showed us where they give way, and code written by AI tools now opens the gaps faster.
01
App
Sign-in, sessions and every form a user can type into.
02
API
Each endpoint asked who is calling and what they may see.
03
Data
What you store, how it is encrypted and who can read it.
04
Access
Admins, teachers and students, each held to their own role.
OWASP top-10 reviewAuth + API testsFindings report + fixes
Get a security reviewPentesting from $1,000
03Products
We run what we build
Our own products, used every day across Zimbabwe, from exam prep to the Shona Bible.
DanhoZIMSEC O Level and A Level past papers, offline.
Sit a past paper
ProvisionalPrepare for the Zimbabwe provisional test, offline.
Try practice test
BhaibheriThe Shona Bible and the hymn book your church sings from.
Read the Bible
KwaunobvaRediscover Shona heritage through totems, practices, and proverbs.
Explore heritage
DenheLive
The record of what Zimbabwe publishes.
SpeedTestLive
Measure your real internet speed and compare local ISPs.
Invalcre Virtual LabsLive
Lab practice for every classroom.
Invalcre SMSBeta
An operating system for Zimbabwean schools.
HomweIn development
Your pocket: hustle money, budgets, and who owes you.
eMaokoLive
Teach and master practical skills with Zimbabwe's finest.
MushandiLive
Connect instantly with Zimbabwe's top service providers.
Shona ASRIn development
Speech recognition for Shona, in training.
20+mobile apps in both app stores
20+web projects shipped
500+hours of support
12products of our own
04Work
Apps and sites we built for clients
Businesses we have built for
AccesshubEngineering Better Mobility: an urban mobility and traffic engineering consultancy in Harare.
In Loving MemoryA memorial web page behind a QR code on a steel plaque, for the people we have lost.
Earth and GreenHealth and wellness consultations, from the first form to a plan.
PBNIBusiness directory and networking platform for economic players.
KakLearn Russian verbs the easy way.
ZimotokaYour reliable on-the-go partner.
TifambePickups and ride shares.
GardarikaDiscover restaurants and cafés.
Musika Go BusinessEngage customers and meet their needs on the go.
Musika GoFind anything local.
BrightushOrder pizza on demand.
Prog-TrackerKeep track of your study progress.
05Releases
What shipped lately: four releases across four projects
September 2026DenheWeb
DenheWebDenhe is live: the record of what Zimbabwe publishes
Zimbabwe's laws, school results, budgets, bank codes, network data and public registers, one page per thing.
Read the release7 changes
September 2026
AccesshubClient work
AccesshubClient workA site for Accesshub, a Harare mobility consultancy
Six pages on its services, projects, team and contact, in light and dark, fast to load and built to be found.
Read the release4 changes
August 2026DanhoAndroid · iOS · Web
DanhoAndroid · iOS · WebDanho is live: ZIMSEC O and A Level past papers, offline
Practise ZIMSEC past papers paper by paper, on the phone and on the web, with answers at the end.
Read the release4 changes
August 2026ProvisionalAndroid · iOS
ProvisionalAndroid · iOSProvisional 2.0: prepare for the Zimbabwe provisional test
The Highway Code reader remembers where you stopped, keeps your bookmarks and highlights, and every reminder opens the right page.
Read the release4 changes
06Contact
Tell us what you are building
We reply within one business day, on WhatsApp or by email.
07Reviews
From the people who use our apps
I’m surprised no one talks about this app when studying for their provisionals. Every question I saw in the VID test was here! Apple users this is your holy grail!
Provisional · App Storethis should be the official study app. very helpful and no ads ,works offline as well. no complaints only high praises, I got mine today. thank you!
Provisional · Google PlayA great application indeed. Very helpful
Provisional · App StoreThis App truly helped me study for my provisional test. I recommend it to anyone who wants to sit for the exam. The application interface is easy to navigate. I scored a perfect score after using this app to study for 5 days
Provisional · App Storegood App for Christians.
Bhaibheri · Google PlayThe best thing ever made loved it
Bhaibheri · App StoreThe App is very good , it helps you answer very fast because of the timer and this is the most important factor to consider when writing a provisional test.
Provisional · Google PlayPerfect app for my needs
Bhaibheri · App StoreActually this app is incredibly useful and the questions and notes in it are very helpful i recommend everyone to use it
Provisional · App Store