When it comes to metronome apps, I have two qualities I look for.
It has to be loud enough to hear over a flute or concertina (bonus points for piccolo!)
The click has to be the furthest thing from annoying
It's surprising how difficult it is to find an app that fits these basic needs. You can't imagine how delighted I was to find the Pro Metronome app!
Thing 1: Volume
The Pro Metronome passed the loudness test. I can hear it over the flute, a concertina and even third-octave piccolo.
Test #1: Pass with flying colours!
Thing 2: Sound
There are 14 sound options available, from a voice counting beat numbers aloud to the standard woodblock/mechanical metronome sound.
Tone option #1 passed my "not annoying" test, so we have a winner!
The Visual Block option lets you colour code your beats within the bar.
Side note: a few of the tones sound a bit "mushy" to me - multiple strikes at the beginning of the tone, so not as precise as I'd like when I'm practising. I would personally avoid those if I'm looking for accuracy (and why else do we use a metronome?). The others are fine, and I like having a mute option for silent practice sessions.
Other Features
Thing 3: Time Signatures
Multiple time signatures are available in the free version, ranging from 1 - 16 for your top number and 1 - 32 for your note value.
You can choose any combination, so if you feel like setting your time signature as 16/32, you have that option.
Subdivisions within the time signature are available in the pro version, but you can get access to a few options in the free version by choosing from the list of preloaded songs in the app.
Thing 4: Practice Timer
Love love love this feature.
You choose the length of time you want the metronome running for, and it will set off a little chime when your time is up. You can choose the times on the buttons or select the 60/custom button to enter your own time period.
I use this when I know I only have a limited amount of time available to practise in a session. If I only have 30 minutes and I need to get 3 things done, I'll decide on the maximum time I have to devote to each element and then set the timer. Keeps me focussed and helps me not run over time.
Thing 5: Tempo
You can dial in your tempo on the main screen (as shown at the top of this page - I'll admit to enjoying the tzappy sound of the turning wheel a lot) or type in your specific tempo on the number pad.
If you don't know the number associated with the tempo you want, there's a handy "TAP" button on the main page (first picture, top of page). Tap on this button until the "KEEP TAPPING" message disappears, and you're all set!
Thanks to Laura of Leading Note Studio for the TAP feature reminder!
This is currently my favourite metronome app. Do you have one you like more? I'd love to hear about it!
All points mentioned above are available in the (current as of time of writing) free version for Android; anything with a *PRO on the screenshots is available in the paid version of the app. There are a few neat features available on the Pro version; check out the app info page on your app store of choice for more details.
Check it out for yourself!