Best not activate the app until just before travelling/boarding your first train of the day. You can still deactivate it. You never know If you fall ill or a strike wave hits the continent again, forcing you to replan a bit. You don't want to accidentally squander the days of your pass :) 

I think I never used the web application "my interrail trip". Best to plan your trip via the Interrail app. (Tab "My Trip", create a new trip, name it. Than you can start adding journeys. See it as your rough planning.

Note that the rail planner app and eurail websites are often wrong and contain false information. Best use a planner like the one of Deutsche Bahn. DB has updated info for most of Europe. Or use the national planners of the respective countries, you'll always have the correct and real time info then. 

Quite some summer timetables won't be available yet. Don't panic if something doesn't show up, but just wait a bit. It'll show up eventually. Or just check for e.g. next week from today, to get an indication of the travel time. Schedules don't change a lot. 

As soon if you have your theoretical planning up on one device, you can create a link that you can share with your fellow travellers. Note that this link does not couple your planning together. If one person updates or you changes the trip planning, on the other device it doesn't update automatically. 

You should only connect that trip to a pass, or activate the pass until just before travelling. 

But it's all explained clearly in this tutorial: https://www.interrail.eu/en/interrail-passes/interrail-mobile-pass/getting-started

Reservations are complete separate from the app and pass. You can already start making them. If you plan taking the Eurostar (London-Paris/Lille/Brussels/Amsterdam), best make reservations asap. There are little to none adequate alternatives for that train.

If you post time, dates, time and the two distinations you want to travel to, we can give you tips how to get seat reservations, how to avoid them, or where to find the cheapest option. Just open a separate topic, followed by your itinerary, if you'lld encounter  difficulties with it. 

In no time a community member will give you plenty of advice how to best tackle it :) 

Here is some useful information from the experienced travellers in the Community regarding both planning, reservations and activation of pass and travel days. 

 Planning

The rail planner is normally not up to date, as it only is updated once a month, so to be sure of the time table you better check the timetable and availability on the websites of the national railways. The bigger national railways, like DB (Germany) SBB (Switzerland) and ÖBB (Austria) cover several countries. 

 Reservations 

I hope this “simple” description will help you understand the App and complements the advice above.

The app has 4 tabs but only 3 of them relate to using your pass as a train ticket, I will leave reservations out of this as they are an extra external process.

The first to discuss is the planner. This is just a timetable of many but not all trains across Europe. It’s main use is , in conjunction with many other planners, to identify routings and train times and to indicate whether separate reservations are needed, optional or not needed. Once you find a train you intend taking you can add it automatically into your Trip (The second tab).

The Trip tab in the app allows you to create a dedicated trip for the duration of your pass. Irrespective of how many excursions you are planning there is only one Trip per pass.

Note the Trip option on the website is totally separate and does not sync or play any part in the app - consider it as nothing more than a jotting pad.

Your trip is your diary of planned trains and needs all your planned trains added before boarding. It is totally flexible and you can add and remove at any time. Trains can be added either from the planner or manually but until you transfer any train to your pass it is just a wish list and is not a ticket or a booking.

Finally there is a tab for your pass. Once you transfer a train from your trip. ideally not before you actually know you are boarding that train, the app creates a travel day and generates a QR code for the day. It also lists the train details below the QR code. This is your ticket to travel on that train and all that is needed for inspection, except of course if the train requires a mandatory reservation or supplement, for which you need separate evidence. As you travel on more trains that day you transfer each one as you board and it is added to the list in your pass. If your current train is not listed it means you have no ticket - the QR code is not enough by itself. I repeat - it is not acceptable to show QR code and say train is listed in your trip because you forgot to transfer it, although many inspectors would be tolerant.

One last point the pass will work without an internet connection so if you are having access problems from a flakey wi-fi sigmal put it in airplane mode. You do though have to access the internet with the app open every couple of days.



There are many subtleties but this is the basic process for all trains.

 

Yorkie, I am in the same position as Zagmund who originally posted this query - a new Interrailer who is baffled by the process for using the Interrail app. I wanted to say how useful I found your explanation, but also to ask a couple of supplementary questions. First, when you say “transfer” a train form your trip, what do you mean? Is this a separate process from attaching the Trip to your Pass? Secondly, is there any way - apart from doing it manually - of duplicating the Trip I have created on my mobile so that my husband can use it too? Thank you for your help

I’m going to recycle an reply I made a couple days ago, that’s similar to your questions, based on a trip I did in summer:

Firstly) This “transfer” @Yorkie mentioned is the following.

Circled in green are the trains I added in my trip. You can tap on the grey ledger to transfer it to your pass. I actually only took a train later that originally planned, so I didn’t need to activate the first journey.

Circled in red are the trains that I effectively used, and that got transferred to the pass.
These generated a qr-code. Note the yellow ledger.

Secondly: Duplication is possible. You can make a link to share the planning in 'My Trip'. Tap the three dots in the right corner, in the dark blue bar (also see above), press "Share as link" and give that link to your fellow traveller. The same planning should appear on his device.
Note if changes occur to your planning, it doesn't update on the device where the trip got shared.

Brendan DB, thanks for your very helpful answer. So I can attach a Trip to my Pass, and when I am actually ready to travel, I transfer the train I am actually using to my Pass? 

Indeed, just like that.

Best do it only minutes before starting to travel or just before boarding the first train of the day, you never know if there’s a hiccup in the services or other reasons complicating your travel. You don’t want to squander any travel days :)

It seems hard at first, but after a couple of times you can really get the hang of it, it can be done in a couple of seconds. :)

Thanks for that clarification Brendan.  It is starting to become clearer now.

If I understand your posts correctly the process looks a little like this -

1. Use the planner to identify a journey (e.g. Brussels to Antwerp on a specific train on a specific day), noting that others have pointed out that the planner is not up to date and you are probably better off looking the journey up on the carriers website (or bahn.de)
2. From the planner, select “Add to trip” or equivalent wording.  Or add it manually if you identified it from the carriers website.
3. Even though the trip is associated with a pass and the trip now contains details of a particular train between two places on a particular day, this journey doesn’t exist from the point of view of my pass.
4. In order to be able to get on my train in Brussels I need to go into the trip and toggle the grey/yellow switch you highlighted above.

If this is the case, then you deserve many thanks and brownie points for explaining what many, many articles on the site did not make clear to me.

David

@zagmund Indeed, perfect summary of how it works. I'm sure you'll become a pro in using the pass!  

To be complete, best add a 5th:

"Show the generated QR code in the tab "My pass" upon inspection."