I’ve had my Fairphone 3+ for five years and it worked fine, but lately it’s been very slow and laggy. My 60 GB storage is full so I can’t take any more photos. And my battery drains very quickly. Using my phone has become so annoying, especially when I need to look up or send something quickly. It’s very noticable when I compare my ‘old’ phone to my family’s iPhones and Fairphones 4…
I was hoping my Fairphone would last for more than at least five years. So now I am debating whether I should I upgrade my Fairphone 3+ with new parts, or buy an entirely new Fairphone 5.
Would a new battery, a microSD card for storage, and a factory reset make my Fairphone 3+ run smooth again? Or would that be a waste of money and time? Is it better to start afresh with a new phone?
It’s good you already provided very helpful information – an internal storage nearly full is a prime suspect for why a smartphone turns laggy. So you already mentioned what I would recommend:
I would recommend you don’t save single-digit Euros and go for at least a 128 or 256 GB card and then make sure you either leave it formatted as it is or format it as portable storage (and notphone storage = internal storage), see ✏ A little guide to... using SD cards. Some random experience with existing cards can be found here ✏ List of compatible micro SD / SDXC cards for FP3
Of course, you could also move some dozen GBs to a different storage medium (computer, cloud, hard drive etc.), but I would recommend to do that in addition to a card, not as an alternative – this way, you can still access your photos on your FP3.
A factory reset can help to get rid of hard-to-find problems that might occupy system ressources, but you can still go to that option after you have gotten yourself an SD card and moved dozens of GB from the internal storage to the card.
A battery replacement is probably not helping with making the device fast again, but once you are at it, you could check yours for signs of bloating: Take it out of the device, place the battery flat on a really flat surface and see if you can make it spin. If it’s easy to make it spin, it is probably showing first signs of bloating and should be replaced – but only for security reasons.
Act right now and free up space if you value your data on the phone!
Android has no precaution against filling up all storage, and then it will essentially block any usage, and it will be a real hassle or even impossible to get the phone back on track without data loss!
The factory reset should do this.
Evaluate battery life again after the factory reset, it might just be ok again. But in case you want to keep the phone, having a spare battery can’t hurt either.
Regarding a microSD, please be aware of our sdcardguide (TLDR: Never format it as internal storage!).
When my FP3 started to struggle I would go into Settings > Storage > Apps and then work through the list of apps, pressing to open each one and then clearing the cache if was of a non-trivial size. That used to free up a few gigabytes and the phone would be perkier for a while…
I have a SD card and lots of free space on my FP3+, but my phone is annoying slow too. I use CCcleaner to get rid of unused files and cache. I’m going to follow this topic to learn.
That could be a problem and is normally rather adding more background noise than adding a real value to speed something up. Beside the fact that it comes with 12 Google etc tracker (at least in the free-version). I personally would recommend against such tools.
I replaced my battery twice already, always after a bit over two years. It helped each time with the drain
Didn’t help with the storage, though. And even though I added a SD, that only helped for a while. I am thinking of upgrading to something in the not too distant future.
portable storage (and not 
phone storage = internal storage), see 
