1. Can I use SUNRISE Contacts on an iOS device?
Yes. In fact, as soon as Apple removed the free web publishing (i.e. WebDirect-like) feature known as Instant Web Publishing (IWP) in the standard and advanced versions of FileMaker Pro some years back (and would have been the ideal solution for budding and budget-conscious families and small businesses in delivering data online to a small team), the company introduced the much cheaper option known as FileMaker Go. It is a kind of compensation to customers for the rather significant loss of the IWP feature, but deep down it is a quiet strategy to encourage people to buy iPads and/or iPhones and give Apple more profit in selling FileMaker Pro and FileMaker Server (not because Apple was losing money from selling the product, but because it is a shareholder company in desperate need to maximise profit wherever it can). On the positive side, FileMaker Go is free (for now) and will allow the running of your databases on any number of iOS devices. Thanks Apple! You are too kind.
For Android users, no such option exists. Sorry guys. Apple hasn't been kind to you as yet. Your best option for now is to use FileMaker Server to access the databases on a web browser.
Since Apple has requested its subsidiary company Claris to remove the Runtime feature, there is a distinct hole left behind for Windows users who use the Runtime app. With nothing free to run a FileMaker database and with Windows users feeling like second-rate citizens compared to iOS users, Claris has been permitted to fill the gap. As of 5 August 2020, Claris gave the first indications in its Keynote presentation at Claris Engage 2020 that it will create a FileMaker Go for Android. And yes, it will be free. Unfortunately it won't run on Windows. A kind of mediocre compensation for the loss of something free on Windows. For Apple users, the release of Apple Silicon chips for new Macs at the end of 2020 will allow FileMaker Go to run on macOS. So this is going to be the equivalent of a Runtime app (without plug-ins). However, until Microsoft sees Apple has converted enough users to the AMD-based processor, it will be a while before anyone can run FileMaker Go as a native app on Windows. The alternative is to try one of these solutions as a way to emulate the Android environment.
At any rate, the new FileMaker Go for Android should not be a major engineering feat, as all Apple has to do is do a straight C++ compilation of the original FileMaker Go for iOS with only a few changes needed under-the-bonnet (mainly to connect features like the camera, GPS and other built-in functions to the app). This new app should be ready by mid-2021. (1)
In the meantime, it is a poor decision to lose the Runtime feature at this stage for Windows users. More of a case of Apple determination to prevent a Runtime app compiled in the new AMD/Apple Silicon environment. Apple does not want to see a Runtime available in any form on the new Macs. Consequently, the decision to remove the Runtime app on the Mac has affected Windows users. (2)