Alright, got the app to try it out.
Thoughts
1) Paladin and Ranger both have spells listed up to level 9, even though they cannot get higher than 5. Not a real issue, just something you might be able to clean up.
2) The brushed steel looks fine, and is perfectly serviceable. The only reason one might change it is for aesthetic purposes.
3) On functionality, it works fine. One quibble, personally, is that you have attack Bonus listed in the key as "Battk1", making it read in my mind as "Bonus attack". Maybe I am alone on that, so you will want other opinions on it, but you might want to think about changing it to "AttkB1", or you could assume they understand that the attack bonus goes with the attack of the bar it is in, and just have it say "AtkBns".
4) If you do decide to change the background in other areas of the app, I would keep the brushed steel pattern to put in the equipment section, as that would give a very "Anvil" feel, which seems appropriate, rather than the flat black behind the wood design. You might even go a step further (forgive me for offering you more work) and have a different background for different areas of the app. So, the magic area could be a leather pattern, like a spell tome, while the monster area is stone, and the equipment area is metal. Just aesthetic thoughts though, I am thinking aloud in case you like the ideas. I do know enough, in my tiny amount of experience, to know that changing any of these things would require minor adjustments to other pieces of the same area though, to make them stand out properly against brown/red rather than grey, so I do understand that I am talking about a lot of work for minor benefits.
5) If the SRD permits it (not familiar with it personally, so I don't know) You might want to include some essential rules for some of the equipment, like a note on what the Range increments for the ranged weapons mean. If the SRD does not permit that, nevermind.
6) Lastly, the spells say "See Sourcebook" for parts of them. Does the SRD prevent you from telling what page, as you did the monsters? That would be a nice bit to have, as finding spells tends to be the most annoying part, and one of the main reasons I would want an app like this.
Altogether, it is certainly a nice app, and beyond my capabilities to produce. If you had not specifically asked for constructive advice, I would probably not have mentioned any of this, as I feel a bit dickish for telling you to "fix" things that I have no idea how to do myself. Best of luck, and I look forward to continuing to use it.
EDIT: On a personal note, I feel a bit like a Champion Fighter telling the Wizard that the Fireball would be
so much cooler if he made it green instead of red.
