Native and Cross platform Mobile Outsourcing


There are 6.8 billion cell phones and tablets around the world as of 2016 and this number will continue to grow. This means that even now more than half the population of the world has access to mobile apps.

Mobile development is a challenging task at times, but when you clearly understand your idea and your developers understand the global mission of your app as well - this is when miracles happen.

Grossum's mobile development team is combined from various specialists - iOS and Android developers, Quality Assurance engineers, and project managers who, being mediators between the business and developers, always advocate on the product's side.

Grossum offering

Grossum offers full-cycle mobile development - starting from interface prototypes and project's architecture to actual development, and subsequent QA, to make sure you have the best product in the end.


We also provide you the high-quality cross platform mobile outsourcing using Ionic or React Native.

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We use InVision and other tools to give the product owner a feel of what the app will look like, helping to identify the user path and streamline the experience.


Development begins before actual development. Architecture is an important step that helps to build the app based on industry and vendor specific standards and make sure the app works on all required platforms.


We have experience with developing native apps for iOS and Android as well as cross-platform mobile apps using Xamarin. Depending on the project requirements, we will discuss with you the best possible solution to make your project be ideal.


Making sure that your project works perfectly and does all that what was expected of it on all platforms you need, our QA engineers check and test the project. This isn't simply "finding errors" but making sure that your project meets the requirements.


Geopak (USA)

Enhance your hunting adventure! With augmented reality, you get to see where your hunting friends are in real-time, including their direction and status. You can also plan your hunt in advance and once the hunt is over, analyze the stats.

CONARH 2015 (Brazil)

CONARH 2015 is the biggest congress in Latin America for Human Resources. i9ação (, which build games for human resources' trainings, got the chance to build the app for the congress. As Goldark and i9ação are partners, we promptly joined forces to make this development possible.

Biudee (Denmark)

An app created to make it easier to monitor and keep one's health and beauty under control.



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Presentation / GitHub