One of the big upsides of using an Android phone is the sheer scope of customisation that is available to users. Rooting your phone and choosing a completely different version of the operating system isn't hard, but otherwise there is a whole laundry list of apps that can change everything from the way your phone looks to the way it works.
Shifu, by Delhi-based The Signals, is one such app, which lets you outsource the job of remembering what's important and when to do it. The app keeps running in the background and tracks how you're using your phone. It also requires access to your phone's calendar. So it knows, for example, that at 9AM every day, you're traveling from home to office, and it knows that you're going to take half an hour to get there.
The developer claims that it can even analyse your commute patterns (detect if you've taken the metro and therefore have time to read, for example) and make suggestions from your to-do list based on all these facts. What makes it powerful is that it's simple and easy to set up, and as you keep using the app, it starts to build patterns based on your usage, and make suggestions accordingly. If there's any actions that you make regularly, then Shifu will start to suggest them to you based on a predictive algorithm, when it thinks you're likely to want to repeat that task - something like calling your driver every evening when it's time to leave office, for example.
Shifu can also detect and identify Wi-Fi networks, this can be used to, say, upload pictures from a party when you connect to any Wi-Fi, to reduce the load on your data connection. Shifu developers also added in a geofencing feature, to allow location-based actions.
This means instead of setting a time, you set reminders according to the amount of time they require, or the location you're in. So, for example, you know that you need to buy shoes from a particular shop in a market. Since it's not urgent, and you keep going to that market, you could set a reminder to alert you to buy shoes, which is displayed whenever you visit that market next.
Or, suppose you want to call your parents, and you know that a call to your parents almost always lasts 10 minutes. Instead of finding an empty 10-minute slot, you can have Shifu send a reminder whenever you have 10 minutes free on your calendar. It'll find time between meetings, when you're not typically busy with something like your commute, and send a reminder.
The app has been around for a while now, but was updated recently, and the newest version (0.6.1) addresses one of the biggest problems with Shifu - the user interface. The earlier versions of Shifu were useful, but they looked like a school kid had been in charge of design. There are other automation apps that look worse, but none that looked like they were made using crayons.
In contrast, the new design is a lot sleeker, taking inspiration from Google's cards-based UI. It looks much more at home on your Android phone, and actually fits in with the flow of things.
Some of the features of Shifu seem a bit pointless - an alert which pops up when you're in the middle of a call might sound useful, but unless you're permanently tethered to a headset, looking at reminders in the middle of a call is simply not convenient.
Similarly, a birthday reminder that pops up when you're free sounds useful, but just about every service with a calendar is going to remind you about birthdays, so it's unlikely that you really need this one.
Call reminders that go through your missed calls and remind you to call people based on the order of importance when you're between meetings is a godsend though, particularly if you've used Shifu for a while.
The new update also claims to have less of an impact on the battery life - it's a little harder to judge that because the day to day usage between trying the older version and this version has changed a lot as well. However, it does appear to be the case.
The big selling point to Shifu is that it's fairly simple to get it running to meet your needs. There are more powerful apps which can do the same things, but getting an app like Llama to work means fiddling with lots of text only menus, and while it's a lot more powerful, it's also a lot more complicated.
If you're looking for something that's simple and effective, then Shifu is a good choice, and it's free, so there's nothing to lose.