When assembled, the phone would have a screen covering the entirety of the front, volume buttons and headphone jacks along the outer edge, and bloks clicked into the back, forming a rectangular block shape overall.

One challenge this concept faces is the great amount of money and manufacturing required in order to make the Phonebloks system a viable competitor with other major smartphone developers.

[7] This extra distance could lead to drops in signal quality, lower data transfer speeds and increased power consumption due to added interfacing resistance.

In addition, the quality of connection needed would require expensive Pogo pins and sockets, and developing a system to allow the user to arbitrarily place bloks would be very difficult.

Despite Hakkens' stated goal of lessening electronic waste,[8] critics have argued that, if put into practice, the concept could actually increase e-waste output.

After exceeding his goal of 900,000 supporters on Thunderclap by October 2013, Hakkens started collaborating with Motorola on Project Ara, a more practical modular smartphone system consisting of an endoskeleton with slots on the back where bloks can slide in.