If you have a domestic battery storage system, you will want south facing solar, angled at about 30 degrees, the case is obvious, you get the longest duration and highest power from this orientation. So when charging batteries, cars or heating your hot water tank you are best with south facing solar. There is a downside if you are not charging or storing, south facing gives you all this power during the hours of the day when you generally don't need it, moreover your power company doesn't want or need it either, so you'll get little (£) for it.
Rather then install for maximum power yield, we could consider asking, when do we need power. The answer is, the morning, perhaps at lunchtime and in the late afternoon and evening. So if you are installing plug-in solar (Balcony Solar) consider 'east facing' for morning power boost or 'west facing' for an afternoon or early evening boost. These orientations give you the best chance to use and not export your generation and therefore reduce your import of energy from your electric provider. Should you generate more then you need you could consider an immersion diverter or a plug-in home solar battery system, these allow you to store your excess energy and deliver it to you in the evenings.
What if you are installing on a wall (vertical) and not a roof (~30-45 degrees)? Wall, fence or balcony solar is generally installed vertical or near vertical, this means that it is better suited to when the sun is low in the sky, this of course, occurs in the mornings and evenings, giving you a better yield at those times. When vertical installations are south facing, they do lose peak power because the sun is at its highest and this will reduce the power capture of the panels, simply due to the angle of incidence.