iOS map (any) draw route direction (arrows on lines)

Question

After some attempts to draw arrows above lines for showing direction on route (any map: Google, Apple, mapquest, Yandex) I got two common problems:

1) The arrows images loose its quality on zooming in

2) Arrows width and line width are not synchronized when zooming in and out. I mean, that my arrows are represented by annotations, and in any map I can't synchronize the arrow and line width together when zooming.

After some research I found this app for iOS:

And found HERE map javascript API

They look similar and iOS app map behave exactly what I want to do with my app.

Are there any assumptions how to do that in iOS?

Here are my results:

Persecution

it would be really helpful to if you could add the solution here. :-) – Rawden