Messaging app with smiles editor based on photos

Objective:

Build a messenger app like WhatsApp, but with an additional key feature: smile editor where a user can create cool emoticons with own faces and different items available in built-in shop.
Monetization strategy is selling assets and stickers for emoticon editor (in-app purchases).
One of the main requirements was to build a high load and scalable solution, being able to manage 100k+ users.

Solution:

Firstly we analyzed client’s requirements, prepared a software requirements specification and then moved to the development process including design and QA.
In 4 months from the project beginning we made a quality working solution, a first app version (MVP – minimum viable product), according to the spec and submitted it to app store review. At the next project stage we made:
– restrictions for abuse and offensive content
– opportunity to restore purchases
– contact processing
– integrational tests
– performance testing and JMeter
There were a lot of changes in the project requirements during the development process, hereupon we didn’t have a completed design prototype for quite a long time.
What concerns functionality, we can identify the following significant modules:
– application and interface
– sending messages and libraries (MQTT and AMQT)
– photo editor
– sticky notes: purchasing, recovery
– interlinking between accounts
– group chats

Result:

We built efficient native applications meeting all customer’s requirements. During the working process we gained useful experience involving:
– update design prototype as many times as needed if a client changes something in the requirements
– working with continuous integration
– working with integrational tests
– deeping into performance testing and JMeter