Others have covered the lighting aspects, but one thing no-one has mentioned yet is **perspective**

Please excuse the abysmal quality of these examples, they are merely to illustrate one point - that you cannot do close-up photos with a phone*.  
From close up - the same as if you do a selfie - you get a huge amount of distortion due to the *percentage* difference in distances from the lens. In a selfie, that's why you always get that 'big nose, little ears' look.

I don't just happen to have any bullets in my drawer, but I do have a couple of vape refills. These are about 65mm tall. My intent, though very, very approximate, is to show what happens with anything not in the centre of the image when you get too close. These pictures attempt to get one item in the centre & one on the edge of frame… nothing else.

iPhone photo, taken from maybe 100 mm away. I'm not *quite* as square to the subject as I should be, but it nicely accentuates the failure, and anyway the tops of the bottles look 'bigger' than the bottoms from this close…

[![enter image description here][1]][1]

A phone camera is about an 18mm, give or take, if you use approximate 'proper' camera [35mm frame] equivalency. Look how much 'lean' & 'smear' [lack of squareness] there is on the bottle on the right. The table is, of course, to all intents & purposes… flat.  You'll see this effect any time you try with a phone to take a group shot of half a dozen people having a fun night out ;) From the distance needed to get a 'party group shot' you won't see so much of the lean, but you will see the smear, a widening of things & people at edge of frame. This **is** to do with the lens as much as the distances involved.

I did the same, positioning in [roughly] the same line as the last shot, but from much further away, using a 350mm lens [35mm equivalent]. This meant that to fill the frame the same way, I had to be about 1m away. Ten times further away, meaning all my percentage differences in distance to object became insignificant. 

[![enter image description here][2]][2]

Ignoring all other aspects of this photo, look how 'straight' the right hand bottle is now, compared to the phone photo.  
This apparent 'straightening' is not entirely because I used a longer or even a 'better' lens, but predominantly because I was further away. The white background being apparently closer is an additional aspect of this perspective change. It is actually the same distance. 

You can attempt the same with a phone only by increasing your distance to subject, then cropping afterwards. This is 'the same' as using a longer lens, but you lose definition by cropping.


<sup>*You might have a get out of jail free card if you have a 'posh' phone with multiple lenses.</sup>  



  [1]: https://i.sstatic.net/RRHosm.jpg
  [2]: https://i.sstatic.net/r94Tnm.jpg