Engineering new solutions for powering smart portable devices is key to sustain billion-scale connected objects and to provide a greener alternative to batteries. Indoor Photovoltaics (PVs) - with a projected market of $850 million by 2023 - relying on conversion of visible indoor light- can sustain this challenge, capitalizing on the development of flexible, semi-transparent, colored and easily integrated energy generation devices. Despite the urgency and the large market potential, current PV technologies mostly fail, leveraging on rigid and bulky systems fabricated by energy-intensive processes (i.e. Silicon PVs) or on carbon-based technologies not yet in the market for their insufficient durability. Hybrid perovskites with wide band gap (2eV), with their easy tunability, structural flexibility, and lightweight, hold the potential for a transformative solution in visible PVs. However, lower efficiency compared to low-band gap ones, reliance on toxic elements and insufficient stability hamper their scaling up. ELOW-DI faces this challenge by engineering the perovskite dimensionality as the key variable to unlock device instability while allowing for efficient visible light conversion. This will be obtained i) by developing intrinsically stable low-dimensional perovskites (LDPs) leveraging on non-toxic elements and stable hydrophobic units and 2) by controlling material nucleation and consequent thin film morphology to obtain vertically oriented crystalline nanopillars, essential to ensure efficient charge extraction in the device while reducing unwanted recombination. Upon the demonstration of the proof of concept on lab-scale, research will be moved to a completely new direction by engineering large area devices while ensuring the scalability of the nanoscale material properties. ELOW-DI is timely, and it will generate the new multidisciplinary knowledge from material to device engineering- which is now needed for the next-gen of indoor PV solutions.